4411-0069
Version 5.G
September 12, 2011

*4411-0069*

Copyright 2003-2011

Princeton Instruments, a division of Roper Scientific, Inc.
3660 Quakerbridge Rd
Trenton, NJ 08619
TEL: 800-874-9789 / 609-587-9797
FAX: 609-587-1970

All rights reserved. No part of this publication may be reproduced by any means without the written
permission of Princeton Instruments, a division of Roper Scientific, Inc. ("Princeton Instruments").
Printed in the United States of America.
IPLab is a trademark of Scanalytics, Inc.
LabVIEW is a registered trademark of National Instruments, Inc.
Macintosh is a registered trademark of Apple Computer, Inc.
Microsoft, Windows and Windows Vista are registered trademarks of Microsoft Corporation in the
United States and/or other countries.
Nikon is a registered trademark of Nikon, Inc.
Programmable Timing Generator and PI-MAX2 are trademarks, and PI-MAX and PVCAM are registeredtrademarks of Roper Scientific, Inc.
Scientific Imaging ToolKit and SITK are trademarks of R Cubed Software Consultants, LLC.
TAXI is a registered trademark of AMD Corporation.
The information in this publication is believed to be accurate as of the publication release date. However,Princeton Instruments does not assume any responsibility for any consequences including any damages
resulting from the use thereof. The information contained herein is subject to change without notice.
Revision of this publication may be issued to incorporate such change.

Table of Contents
Attention! ........................................................................................................... xv
Chapter 1 Introduction ...................................................................................... 17
PI-MAX System Components .......................................................................................... 17
Camera Head .............................................................................................................. 17
ST-133 Controller ...................................................................................................... 18
Cables ......................................................................................................................... 18
Summary of PI-MAX Data Acquisition ........................................................................... 19
Safety Information ............................................................................................................ 20
Safety Related Symbols Used in This Manual ........................................................... 20
Grounding and Safety................................................................................................. 21
Intensifier Modes and Safety ...................................................................................... 21
Audible Alarm ............................................................................................................ 21
High Intensity Light Damage ..................................................................................... 22
Precautions ........................................................................................................................ 22
Cleaning and Maintenance................................................................................................ 22
Cleaning the Controller and Camera .......................................................................... 22
Cleaning Optical Surfaces .......................................................................................... 23
Flushing and Refilling the Intensifier Chamber ......................................................... 23
Repairs .............................................................................................................................. 23
Manual Organization ........................................................................................................ 24

Chapter 2 Installation Overview ....................................................................... 27
Chapter 3 System Setup ................................................................................... 33
Introduction....................................................................................................................... 33
Dangers and Warnings ...................................................................................................... 33
Unpacking the System ...................................................................................................... 33
Checking the Equipment and Parts Inventory................................................................... 33
System Requirements ....................................................................................................... 34
Environmental ............................................................................................................ 34
Ventilation .................................................................................................................. 34
Power.......................................................................................................................... 35
Host Computer ........................................................................................................... 35
Verifying Controller Voltage Setting................................................................................ 36
Mounting the PI-MAX...................................................................................................... 37
Imaging Applications ................................................................................................. 37
Spectroscopy Applications ......................................................................................... 37
Microscopy Applications ........................................................................................... 37
Installing the Application Software .................................................................................. 38
Setting up the Communication Interface .......................................................................... 38
Setting up a PCI Interface .......................................................................................... 38
Setting up a USB 2.0 Interface ................................................................................... 40
Connecting the Interface (Controller-Computer) Cable ................................................... 42
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TAXI® Cable (6050-0148-CE) ................................................................................... 42
USB 2.0 Cable (6050-0494) ....................................................................................... 42
Connecting the Detector-Controller Cable ....................................................................... 42
Connecting to the Timing Generator ................................................................................ 43
PTG ............................................................................................................................ 43
DG535 ........................................................................................................................ 43
Making the Coolant Circulator-Camera Connections ....................................................... 44
Entering the Default Camera System Parameters into WinX (WinView/32,
WinSpec/32, or WinXTest/32) ..................................................................................... 44

Chapter 4 First Light ......................................................................................... 47
Introduction....................................................................................................................... 47
Required Equipment and Cables ....................................................................................... 47
Cable Connections ............................................................................................................ 48
Before Turning on the System .......................................................................................... 48
Turning on the System and Setting Up the Software ........................................................ 49
Configuring the Software for Shutter Mode Operation .................................................... 49
Setup menu ................................................................................................................. 49
Acquisition menu ....................................................................................................... 50
Pulser .......................................................................................................................... 50
Pre-Acquisition Check ...................................................................................................... 51
Room Illumination ..................................................................................................... 51
If Imaging with a Lens ............................................................................................... 51
If Taking Spectra ........................................................................................................ 51
Initial Data Acquisition ..................................................................................................... 51
Focusing ............................................................................................................................ 52
Final Comments ................................................................................................................ 52

Chapter 5 General Operation Factors ............................................................ 53
Introduction....................................................................................................................... 53
Data Acquisition Sequence ............................................................................................... 53
USB 2.0 and System On/Off Sequences ........................................................................... 54
Pre-Exposure Removal of Accumulated Charge .............................................................. 54
Introduction ................................................................................................................ 54
Dark Charge ............................................................................................................... 54
Clean Cycles ............................................................................................................... 55
Continuous Cleans Cycles .......................................................................................... 56
Shutter Compensation Time ............................................................................................. 57
Temperature Control ......................................................................................................... 57
Cooling Method.......................................................................................................... 57
Setting the Temperature ............................................................................................. 58
Exposure ........................................................................................................................... 58
Exposure with an Image Intensifier............................................................................ 59
Saturation ................................................................................................................... 59
Background Subtraction ................................................................................................... 59
Readout of the Array......................................................................................................... 60
Full Frame Readout .................................................................................................... 60
Interline Readout ........................................................................................................ 61
Binned Readout (Hardware Binning) ......................................................................... 64
Software Binning .............................................................................................................. 66

Table of Contentsv

Digitization ....................................................................................................................... 67
Experiment Setup|Main .................................................................................................... 67
Exposure Time ........................................................................................................... 67
Number of Images/Spectra and Accumulations ......................................................... 68
CCD Readout ............................................................................................................. 68
Amplifier .................................................................................................................... 68
Intensifier Gain ........................................................................................................... 68
Intensifier Mode ......................................................................................................... 68
Experiment Setup|Timing ................................................................................................. 69
Timing Mode .............................................................................................................. 69
Shutter Control ........................................................................................................... 69
Fast Mode or Safe Mode ............................................................................................ 69
Delay Time ................................................................................................................. 70
Wait for TTL and TTL Line ....................................................................................... 70
Edge Trigger ............................................................................................................... 70

Chapter 6 Shutter Mode Operation .................................................................. 73
Introduction....................................................................................................................... 73
Cabling .............................................................................................................................. 73
Shutter Control .................................................................................................................. 73
Timing Modes ................................................................................................................... 74
Timing Modes and Cleans/Continuous Cleans ................................................................. 75
Free Run ..................................................................................................................... 75
External Sync ............................................................................................................. 76
Internal Sync (PTG) ................................................................................................... 78
External Triggering ........................................................................................................... 78

Chapter 7 Gated Operation with a PTG ........................................................... 81
Introduction....................................................................................................................... 81
Precautionary Measures .................................................................................................... 82
Intensifier Modes and Safety ...................................................................................... 82
Alarm.......................................................................................................................... 82
Timing Mode .................................................................................................................... 83
Fast Gating ........................................................................................................................ 83
MCP Bracket Pulsing........................................................................................................ 85
Introduction ................................................................................................................ 85
Bracket Pulsing in LIF Measurements ....................................................................... 86
Bracket Pulsing in Nanosecond Pump Probe Experiments ........................................ 86
Limitations of Bracket Pulse Gating .......................................................................... 86
Impact of Bracket Pulsing on Delay........................................................................... 87
Setup ........................................................................................................................... 87
MCP Gating ...................................................................................................................... 88
Introduction ................................................................................................................ 88
Setup and Operation ................................................................................................... 89
Gain Variation ............................................................................................................ 89
Fluorescence Experiment ........................................................................................... 89
500 ps Gating Option ........................................................................................................ 91
Additional Experiments .................................................................................................... 92
Introduction ................................................................................................................ 92

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Procedure for Setting up and Performing a Swept Gate Experiment (Fixed
Width, Variable Delay) .............................................................................................. 93
Procedure for Setting up and Performing a Single Shot Experiment ....................... 102
Procedure for Setting up and Performing a Swept Gate Experiment (Variable
Width, Variable Delay): ........................................................................................... 105
Procedure for Setting up and Performing a Static Gate Experiment (Fixed
Width, Fixed Delay) ................................................................................................. 105

Chapter 8 Gated Operation with a DG535 ..................................................... 107
Introduction..................................................................................................................... 107
Precautionary Measures .................................................................................................. 108
Intensifier Modes and Safety .................................................................................... 108
Alarm........................................................................................................................ 108
DG-535 and Gate Mode Overview ................................................................................. 109
Timing Modes ................................................................................................................. 109
External Sync ........................................................................................................... 109
External Sync with Continuous Cleans .................................................................... 111
DG535 Gating Setup ....................................................................................................... 111
Fast Gating ...................................................................................................................... 113
MCP Bracket Pulsing...................................................................................................... 115
Introduction .............................................................................................................. 115
Bracket Pulsing in LIF Measurements ..................................................................... 116
Bracket Pulsing in Nanosecond Pump Probe Experiments ...................................... 116
Limitations of Bracket Pulse Gating ........................................................................ 116
Impact of Bracket Pulsing on Delay......................................................................... 117
Setup ......................................................................................................................... 117
MCP Gating .................................................................................................................... 117
Introduction .............................................................................................................. 117
Setup and Operation ................................................................................................. 118
Gain Variation .......................................................................................................... 118
Fluorescence Experiment ......................................................................................... 118

Chapter 9 Kinetics Operation ......................................................................... 121
Introduction..................................................................................................................... 121
Masking .......................................................................................................................... 121
Shutter Mode and Kinetics.............................................................................................. 121
Introduction .............................................................................................................. 121
Free Run ................................................................................................................... 121
Single Trigger ........................................................................................................... 122
Multiple Trigger ....................................................................................................... 122
Array Readout ................................................................................................................. 123
PTG Burst Mode ............................................................................................................. 124
One Shot Experiments .................................................................................................... 125
Gate Mode Experiments - Examples .............................................................................. 126

Chapter 10 PI-MAX2 DIF Camera (Double Image Feature) .......................... 129
Introduction..................................................................................................................... 129
Requirements .................................................................................................................. 129
Interline CCD Operation ................................................................................................. 129
Timing Modes ................................................................................................................. 130

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Single Trigger Mode ................................................................................................ 130
Dual Trigger Mode ................................................................................................... 131
Setup ............................................................................................................................... 132
Hardware .................................................................................................................. 132
Software ................................................................................................................... 132
Operation ........................................................................................................................ 132
Single Trigger Mode ................................................................................................ 132
Dual Trigger Mode ................................................................................................... 133
Tips and Tricks ............................................................................................................... 134

Chapter 11 Tips and Tricks ............................................................................ 135
Introduction..................................................................................................................... 135
Overexposure Protection................................................................................................. 135
Signal Delay.................................................................................................................... 135
Introduction .............................................................................................................. 135
Time Budgets ........................................................................................................... 135
Measuring Coincidence ............................................................................................ 136
Adjusting the Signal Delay....................................................................................... 137
Optimizing the Gate Width and Delay ..................................................................... 138
Lasers .............................................................................................................................. 138
Free Running Lasers................................................................................................. 138
Triggered Lasers ....................................................................................................... 139
Jitter .......................................................................................................................... 139
Inhibiting the Pulser during Readout .............................................................................. 139
Lens Performance ........................................................................................................... 139
Throughput ............................................................................................................... 140
Resolution................................................................................................................. 140
Depth of Field........................................................................................................... 140
Baseline Signal ............................................................................................................... 140
Temperature Lock ........................................................................................................... 141
Intensifier Alarm ............................................................................................................. 141
Preamplifier Output Mode .............................................................................................. 142

Chapter 12 Microscopy Applications ............................................................ 143
Introduction..................................................................................................................... 143
Mounting the Camera on the Microscope ....................................................................... 143
F-Mount .................................................................................................................... 144
C-Mount ................................................................................................................... 146
Operation ........................................................................................................................ 146
Xenon or Mercury Arc Lamp Precautions ............................................................... 146
Focusing the Microscope.......................................................................................... 146
Adjusting the Parfocality of the Camera .................................................................. 147
Imaging Hints ................................................................................................................. 147
Fluorescence ................................................................................................................... 147
Microscopes and Infrared Light ...................................................................................... 148

Chapter 13 TTL Control .................................................................................. 149
Introduction..................................................................................................................... 149
TTL In ............................................................................................................................. 149
Buffered vs. Latched Inputs ............................................................................................ 150

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TTL Out .......................................................................................................................... 150
TTL Diagnostics Screen ................................................................................................. 151
Hardware Interface ......................................................................................................... 151
Example .................................................................................................................... 152

Chapter 14 System Component Descriptions .............................................. 153
Introduction..................................................................................................................... 153
PI-MAX Camera ............................................................................................................. 153
Mount Adapters ........................................................................................................ 153
Switches, Connectors and Indicators........................................................................ 153
ST-133 Controller ........................................................................................................... 155
Interface Card ................................................................................................................. 161
Pulser .............................................................................................................................. 161
Spectrograph ................................................................................................................... 162
Cables ............................................................................................................................. 162
Application Software ...................................................................................................... 164
User Manuals .................................................................................................................. 164

Chapter 15 Troubleshooting .......................................................................... 165
Introduction..................................................................................................................... 165
Alarm Sounds Sporadically ............................................................................................ 166
Alarm Sounds Continuously ........................................................................................... 166
Baseline Signal Suddenly Changes ................................................................................. 166
Camera Stops Working ................................................................................................... 166
Camera1 (or similar name) on Hardware Setup dialog................................................... 167
Changing the ST-133 Line Voltage and Fuses ............................................................... 168
Controller Is Not Responding ......................................................................................... 169
Data Loss or Serial Violation .......................................................................................... 169
Data Overrun Due to Hardware Conflict message.......................................................... 169
Data Overrun Has Occurred message ............................................................................. 170
Demo is only Choice on Hardware Wizard:Interface dialog (Versions 2.5.19.0
and earlier)................................................................................................................ 170
Demo, High Speed PCI, and PCI(Timer) are Choices on Hardware
Wizard:Interface dialog (Versions 2.5.19.0 and earlier) .......................................... 172
Detector Temperature, Acquire, and Focus are Grayed Out (Versions 2.5.19.0
and earlier)................................................................................................................ 174
Error Creating Controller message ................................................................................. 175
Error Occurs at Computer Powerup ................................................................................ 175
Excessive Readout Noise ................................................................................................ 177
No CCD Named in the Hardware Wizard:CCD dialog (Versions 2.5.19.0 andearlier) ...................................................................................................................... 178
Program Error message ................................................................................................... 178
Removing/Installing a Plug-In Module .......................................................................... 179
Securing the Detector-Controller Cable Slide Latch ...................................................... 181
Serial violations have occurred. Check interface cable. ................................................. 182
Temperature Lock Cannot be Achieved or Maintained .................................................. 182

Appendix A Specifications ............................................................................. 183
General ............................................................................................................................ 183
Computer ........................................................................................................................ 185

Table of Contentsix

Operating Environment................................................................................................... 186
Controller ........................................................................................................................ 186
Internal Pulser ................................................................................................................. 188

Appendix B Outline Drawings ........................................................................ 189
PI-MAX/PI-MAX2 ......................................................................................................... 189
ST-133A Controller ........................................................................................................ 190
ST-133B Controller ........................................................................................................ 191

Appendix C Software ...................................................................................... 193
Introduction..................................................................................................................... 193
Camera State ................................................................................................................... 193
Main tab (Experiment Setup on Acquisition menu) ....................................................... 194
Pulsers dialog .................................................................................................................. 195
PTG dialog ...................................................................................................................... 196
DG535 dialog.................................................................................................................. 196

Appendix D C-Mount and F-Mount Adapters ............................................... 199
Attaching the C-Mount or F-Mount Adapter to the PI-MAX ......................................... 199
Mounting the Lens .......................................................................................................... 200
Mounting Orientation ..................................................................................................... 201
Focusing .......................................................................................................................... 201

Appendix E Spectroscopy-Mount and Spectrograph Adapters ................. 203
Spectroscopy-Mount Adapter ......................................................................................... 203
Spectrograph Adapters .................................................................................................... 204
Spectrograph-Detector Focusing .................................................................................... 204
Acton (Sliding Tube) ...................................................................................................... 206
Acton (C-Mount Adapter)............................................................................................... 207
Chromex 250 IS .............................................................................................................. 208
ISA HR 320 .................................................................................................................... 209
ISA HR 640 .................................................................................................................... 210
SPEX 270M .................................................................................................................... 211
SPEX 500M .................................................................................................................... 212
SPEX TripleMate ............................................................................................................ 213

Appendix F IVUV Detector .............................................................................. 215
Introduction..................................................................................................................... 215
Nitrogen Purging of the Detector .................................................................................... 215
Dryness Requirement ............................................................................................... 215
Backfilling ................................................................................................................ 216

Appendix G USB 2.0 Limitations ................................................................... 217
Appendix H Glossary ...................................................................................... 219
Declarations of Conformity ............................................................................ 225
PI-MAX with ST-133 and PTG ...................................................................................... 226
PI-MAX with ST-133 ..................................................................................................... 227

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PI-MAX2 with 16-Bit 5 MHz ST-133 ............................................................................ 228

Warranty & Service ......................................................................................... 229
Limited Warranty ............................................................................................................ 229
Basic Limited One (1) Year Warranty ..................................................................... 229
Limited One (1) Year Warranty on Refurbished or Discontinued Products ............ 229
XP Vacuum Chamber Limited Lifetime Warranty .................................................. 229
Sealed Chamber Integrity Limited 12 Month Warranty........................................... 230
Vacuum Integrity Limited 12 Month Warranty ....................................................... 230
Image Intensifier Detector Limited One Year Warranty .......................................... 230
X-Ray Detector Limited One Year Warranty .......................................................... 230
Software Limited Warranty ...................................................................................... 230
Owner's Manual and Troubleshooting ..................................................................... 231
Your Responsibility.................................................................................................. 231
Contact Information ........................................................................................................ 232

Index ................................................................................................................. 233

FiguresFigure 1. Typical Standard PI-MAX System Components.............................................. 17
Figure 2. Major Components of the Intensifier-CCD ...................................................... 19
Figure 3. PI-MAX with PTG System Diagram ............................................................... 29
Figure 4. PI-MAX2 with PTG System Diagram.............................................................. 29
Figure 5. Gen II PI-MAX with DG535 System Diagram ................................................ 30
Figure 6. Gen II PI-MAX2 with DG535 System Diagram .............................................. 30
Figure 7. Gen III PI-MAX with DG535 System Diagram ............................................... 31
Figure 8. Gen III PI-MAX2 with DG535 System Diagram ............................................. 31
Figure 9. Power Module .................................................................................................. 36
Figure 10. WinView/32 Installation: Interface Card Driver Selection ............................ 38
Figure 11. Camera Detection Wizard - Welcome dialog ................................................. 45
Figure 12. RSConfig dialog ............................................................................................. 46
Figure 13. Hardware Setup wizard: PVCAM dialog ....................................................... 46
Figure 14. Block Diagram of Signal Path in Standard PI-MAX System ......................... 53
Figure 15. Clean Cycles in Free Run Operation .............................................................. 55
Figure 16. Timing Diagram: External Sync without Continuous Cleans ........................ 56
Figure 17. Timing Diagram: External Sync with Continuous Cleans ............................. 57
Figure 18. Full Frame at Full Resolution ......................................................................... 61
Figure 19. Overlapped Mode Exposure and Readout ...................................................... 62
Figure 20. Non-Overlapped Mode Exposure and Readout .............................................. 63
Figure 21. 2 × 2 Binning for Full Frame CCD ................................................................ 65
Figure 22. 2 × 2 Binning for Interline CCD..................................................................... 66
Figure 23. Experiment Setup|Main tab ............................................................................ 67
Figure 24. Experiment Setup|Timing dialog .................................................................... 69
Figure 25. Safe Mode and Fast Mode Operation ............................................................. 71
Figure 26. Clean Cycles in Free Run Operation .............................................................. 75
Figure 27. Flowchart of Two External Sync Timing Options in Shutter Mode .............. 76
Figure 28. Timing Diagram: External Sync ..................................................................... 76
Figure 29. Timing Diagram: External Sync with Continuous Cleans ............................. 77

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Figure 30. Timing Diagram: Internal Sync (PTG) ........................................................... 78
Figure 31. Timing Diagram: Internal Sync with an External Trigger.............................. 78
Figure 32. PTG Fast Gating Experiment Block diagram ................................................. 84
Figure 33. Fast Gating Measurement Results .................................................................. 84
Figure 34. Timing: Bracket Pulsing ................................................................................. 85
Figure 35. PI-MAX Timing for MCP Bracket Pulsing with PTG Timing Generator ..... 88
Figure 36. MCP Gated Operation Cabling ...................................................................... 90
Figure 37. PI-MAX Timing in MCP Gated Operation with PTG Timing Generator ...... 90
Figure 38. Experiment Setup|Main tab ............................................................................ 91
Figure 39. PTG|Triggers tab ............................................................................................ 91
Figure 40. Repetitive Gating dialog ................................................................................. 92
Figure 41. Experiments with the PI-MAX ....................................................................... 92
Figure 42. Experiment is Master Clock: Hardware Setup and Timing Diagram ............. 94
Figure 43. Hardware Setup: Controller/ Camera and Interface tabs ................................ 95
Figure 44. Define Spectrograph and Install/Remove Spectrographs dialogs .................. 96
Figure 45. Move Spectrograph dialog ............................................................................. 96
Figure 46. Experiment Setup: Main and Timing tabs ...................................................... 97
Figure 47. Experiment Setup: ADC and ROI Setup tabs ................................................. 97
Figure 48. PTG: Triggers and Gating tabs ....................................................................... 98
Figure 49. Sequential Gating Setup and Width/Delay Sequence dialogs ........................ 99
Figure 50. Aux. Trig. Out tab .......................................................................................... 99
Figure 51. Experiment Setup: Timing and Main tabs .................................................... 100
Figure 52. Experiment Results in 3-D ........................................................................... 100
Figure 53. PTG is Master Clock: Hardware Setup and Timing Diagram ...................... 101
Figure 54. Single Shot: Hardware Setup........................................................................ 102
Figure 55. Cleans and Skips: Default Values Loaded ................................................... 103
Figure 56. Experiment Setup: Gain Selected ................................................................. 103
Figure 57. Repetitive Gating Setup: 100 ns Width, 10 ns Delay ................................... 104
Figure 58. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay ............ 104
Figure 59. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay, Binned
Vertically ...................................................................................................... 104
Figure 60. Repetitive Gating Setup dialog ..................................................................... 105
Figure 61. DG535: External Sync, PreOpen, Exposure Time = 0 s............................... 110
Figure 62. DG535: External Sync, PreOpen, Exposure Time > 0 s............................... 110
Figure 63. DG535: External Sync, PreOpen, Cont. Cleans, Exposure Time > 0 s. ....... 111
Figure 64. DG535 Triggers tab ...................................................................................... 111
Figure 65. DG535 Gating tab......................................................................................... 112
Figure 66. DG535 Repetitive Gating Setup dialog ........................................................ 112
Figure 67. DG535 Sequential Gating Setup dialog........................................................ 112
Figure 68. DG535 Comm Port tab ................................................................................. 113
Figure 69. DG535 Fast Gating Experiment Block Diagram .......................................... 114
Figure 70. Fast Gating Measurement Results ................................................................ 114
Figure 71. Timing: Bracket Pulsing ............................................................................... 115
Figure 72. Gating tab ..................................................................................................... 117
Figure 73. MCP Gated Operation Cabling .................................................................... 119
Figure 74. PI-MAX Timing in MCP Gated Operation with DG535 Timing Generator 120
Figure 75. Kinetics in Shutter Mode: Free Run Timing Diagram ................................. 122
Figure 76. Kinetics in Shutter Mode: Single Trigger Timing Diagram ......................... 122
Figure 77. Kinetics in Shutter Mode: Multiple Trigger Timing Diagram ..................... 123
Figure 78. Kinetics Readout .......................................................................................... 124

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Figure 79. Timing Diagram: Experiment 1.................................................................... 127
Figure 80. Timing Diagram: Experiment 2.................................................................... 128
Figure 81. DIF Operation: Single Trigger Timing Diagram .......................................... 130
Figure 82. DIF Operation: Dual Trigger Timing Diagram ............................................ 131
Figure 83. System Diagram: DIF Operation .................................................................. 132
Figure 84. Diagnostic Instruments F-mount adapters .................................................... 145
Figure 85. Bottom clamp secured to relay lens .............................................................. 145
Figure 86. TTL In/Out Connector .................................................................................. 151
Figure 87. TTL Diagnostics dialog ................................................................................ 151
Figure 88. PI-MAX Rear Panel ..................................................................................... 153
Figure 89. PI-MAX2 Rear Panel ................................................................................... 154
Figure 90. Power Switch Location (ST-133A and ST-133B) ........................................ 156
Figure 91. ST-133 (Standard) Rear Panel Callouts........................................................ 157
Figure 92. ST-133 (PI-MAX2) Rear Panel Callouts...................................................... 159
Figure 93. Camera1 in Controller Type (Camera Name) Field ..................................... 167
Figure 94. Power Input Module ..................................................................................... 168
Figure 95. Fuse Holder .................................................................................................. 168
Figure 96. Data Overrun Due to Hardware Conflict dialog ........................................... 169
Figure 97. Hardware Wizard: Interface dialog .............................................................. 171
Figure 98. RSConfig dialog ........................................................................................... 171
Figure 99. Hardware Wizard: PVCAM dialog .............................................................. 172
Figure 100. Hardware Wizard: Interface dialog ............................................................ 172
Figure 101. RSConfig dialog: Two Camera Styles........................................................ 173
Figure 102. Hardware Wizard: PVCAM dialog ............................................................ 173
Figure 103. RSConfig dialog: Two Camera Styles........................................................ 174
Figure 104. Error Creating Controller dialog................................................................. 175
Figure 105. Hardware Wizard: Detector/Camera/CCD dialog ...................................... 178
Figure 106. Program Error dialog .................................................................................. 178
Figure 107. Module Installation..................................................................................... 180
Figure 108. Serial Violations Have Occurred dialog ..................................................... 182
Figure 109. Outline Drawing: PI-MAX/PI-MAX2 with C-mount Adapter .................. 189
Figure 110. Outline Drawing: PI-MAX/PI-MAX2 with F-mount Adapter ................... 189
Figure 111. Outline Drawing: PI-MAX/PI-MAX2 with Spectroscopy-mount Adapter 190
Figure 112. Outline Drawing: ST-133A ........................................................................ 190
Figure 113. Outline Drawing: ST-133B ........................................................................ 191
Figure 114. Camera State dialog.................................................................................... 193
Figure 115. Main tab with PI-MAX camera .................................................................. 194
Figure 116. Pulsers dialog.............................................................................................. 195
Figure 117. PTG dialog ................................................................................................. 196
Figure 118. DG535 dialog ............................................................................................. 196
Figure 119. PI-MAX Standard Nose ............................................................................. 199
Figure 120. C-Mount Adapter........................................................................................ 199
Figure 121. F-Mount Adapter ........................................................................................ 200
Figure 122. F-mount (Nikon) Lens Adapter .................................................................. 200
Figure 123. PI-MAX Standard Nose ............................................................................. 203
Figure 124. Spectroscopy-Mount Adapter ..................................................................... 203
Figure 125. Camera’s Purge Warning Label ................................................................. 215

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TablesTable 1. PCI Driver Files and Locations ......................................................................... 39
Table 2. USB Driver Files and Locations ........................................................................ 42
Table 3. Readout Rates for Kodak 1024 × 1024 Array at 5 MHz ................................... 64
Table 4. Timing Mode, Shutter Control, Ext. Trigger Input for Shutter Mode ............... 74
Table 5. Timing Mode, Shutter Control, and Ext. Trigger Input when a PTG is theTiming Generator ........................................................................................... 83
Table 6. Single Shot Experiment Time Budget ............................................................. 102
Table 7. Timing Mode, Shutter Control, and Ext. Trigger Input when a DG535 is theTiming Generator ......................................................................................... 109
Table 8. Burst Mode Repetition Rate for PI-MAX 512 and PI-MAX 1k Models ......... 125
Table 9. Bottom clamps for different type microscopes ................................................ 144
Table 10. Bit values with decimal equivalents: 1 = High, 0 = Low............................... 150
Table 11. TTL In/Out Connector Pinout........................................................................ 151
Table 12. I/O Address & Interrupt Assignments before Installing Serial Card ............. 176
Table 13. I/O Address & Interrupt Assignments after Installing Serial Card ................ 176
Table 14. Spectrograph Adapters ................................................................................... 205
Table 15. Features Supported under USB 2.0................................................................ 217

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Attention!
WARNING

Intensified CCD detectors, such as the PI-MAX, when biased ON, can be irreparably
damaged if continuously exposed to light levels higher than twice the A/D saturationlevel. Thus it is critical that you not establish conditions that could result in damage tothe intensifier. Although intensified detectors are less prone to damage from backgroundlight when operated gated, they are at significant risk to damage from high-intensity lightsources like a laser. High intensity sources can damage the intensifier before theprotection circuits have time to respond, or even cause spot damage without theprotection circuits acting at all. In Shutter Mode operation, it will be necessary to keep
the lab lighting be subdued when working with an intensified detector. If a sustained
alarm indication occurs when the controller is turned on, either completely cover theintensifier to reduce the light to halt the overload condition, or reduce the laboratory
illumination still further until safe operating conditions are established.

Alarm
To reduce the risk of detector damage, the PI-MAX detector is equipped with an audible
alarm in the detector head, activated when the intensity of light falling on the image
intensifier exceeds a preset threshold. While the alarm is sounding, the photocathode isdisabled. Immediately switch the MCP On/Off switch (on the back of the PI-MAX) to
the OFF position. Cover the detector window and only switch the MCP On/Off switch
to ON after the illumination level has been lowered. If the alarm sounds continuously
even when the illumination level is adequately low, shut the system down and contact thefactory for guidance.
Note: It is normal for the alarm to sound briefly when the system is turned on.

CautionDiscontinue operation and contact the factory at once if sporadic or continuous
unwarranted alarms occur. They may indicate intensifier damage or another situation that
requires immediate attention.

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Chapter 1
Introduction
The Princeton Instruments PI-MAX® Intensified CCD camera is designed for generalmacro-imaging and microscopy imaging applications. It is ideal for applications
involving ultra low light measurements, or measurements of transient effects. PI-MAX
uses a proximity-focused microchannel plate (MCP) image intensifier (Gen II and Gen III
intensifiers available) fiber-optically coupled to a CCD array. The fastest intensifiers canbe gated in as little as 2 ns or less with an exceptionally high on/off light-transmission
ratio. The CCD array provides a low noise, high dynamic range readout device that canbe scanned at a variety of pixel rates. A number of different arrays are available to matchthe PI-MAX to the widest possible range of experimental requirements. In operation, dataacquired by the camera is routed to the computer for processing and display. The
computer controls both the system configuration and data acquisition via software, of
which Princeton Instruments WinView/32 is an example.
Unless otherwise indicated, PI-MAX will be used to refer to both the standard PI-MAX
and the 5 MHz PI-MAX2™ cameras.

PI-MAX System Components
All PI-MAX systems consist of
standard hardware and software aswell as the appropriate interface
hardware for your computer
system. Some PI-MAX systems
also include an optional PTG or
DG535 pulser.

Camera Head
The PI-MAX camera head houses
the CCD and intensifier and it
supplies all of the high voltages
needed to operate the intensifier(see Chapter 3 for more info).
Cooling within the camera head is
Figure 1. Typical Standard PI-MAX System Components
performed by a cooling fan and amulti-stage Peltier cooler that isthermally coupled to the CCD (liquid coolant circulation can also be used for the standard
PI-MAX camera). C-, F-, and spectroscopy mount adapters are available.
The camera can be operated in one the following three modes: Safe mode, Shutter mode, andGate mode. In safe mode, all the high voltages in the camera head are disabled so highintensity light will not damage the intensifier. In Shutter Mode, the intensifier's photocathodeis biased ON for the set Exposure Time and OFF during each readout of the array. In Gatemode, the photocathode is biased on only during the time each gate pulse is applied.
17

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ST-133 Controller
In addition to containing the power supply, the ST-133 Controller contains the analog anddigital electronics, scan control and exposure timing hardware, and controller I/O
connectors, all mounted on user-accessible plug-in modules.
Readout modes supported include full resolution, simultaneous multiple subimages, andnonuniform binning. Single or multiple software-defined regions of interest can also be
tested without having to digitize all the pixels of the array. Completely flexible exposure,set through software, is also fully supported.
The ST-133 contains two analog-to-digital converters (High Speed and Low Noise) andthe choice of A/D converter is software-selectable. After the data is converted, it istransferred directly from the ST-133 to the host computer memory via a high-speed serial
link. (A frame buffer with standard composite video, either RS-170 (EIA) or CCIR,
whichever was ordered, is also provided.) A proprietary Interface card places the datafrom the controller directly into the host computer RAM using Direct Memory Access(DMA). The DMA transfer process ensures that the data arrives at sufficiently high speed
to prevent data loss from the controller. Since the data transfer rate is much higher thanthe output rate from the A/D, the latter becomes the limiting factor for the dataacquisition rate. Once the digital data is in RAM, the image acquisition program cantransfer the image into its own working RAM for viewing and further processing.

Cables

Detector-Controller cable:
PI-MAX: 6050-0336, 15 foot/4.6 meter, 25-pin D
PI-MAX2: 6050-0499 cable set (6050-0492 Signal cable and 6050-0493 Power
cable), 15 footComputer Interface Cable:
TAXI: 6050-0148-CE, 25 foot/7.6 meter orUSB 2: 6050-0494, 16.4 foot/5 meter. Not supported by PI-MAX2.

Computer Interface Card: Princeton Instruments High Speed PCI card or userprovided USB 2.0 interface card.

Manuals: PI-MAX System manual and optional application software manual.
Optional Application Software: Princeton Instruments' WinView/32 or
WinSpec/32 application program.

Optional Pulser: Programmable Timing Generator (PTG) plug-in module (with
PI-MAX to PTG cable) for the ST-133 that eliminates the need for an external timing
generator or a Stanford Research DG535 timing generator with cables.

Chapter 1

Introduction

19

Summary of PI-MAX Data Acquisition

Figure 2. Major Components of the Intensifier-CCD

In the PI-MAX camera, the input image is focused onto the photocathode of an image
intensifier tube. The tube electronically amplifies the image and outputs it, much brighter,as gray-scaled green light. That light is then coupled to the CCD using a fused fiber-optic
bundle from the output of the image intensifier to the front side of the CCD window. The
image at the output of the image intensifier is translated to the input of the CCD at the same
size.* After being detected by the CCD, the image is read out to the Controller, where it isdigitized and transferred to the computer for processing via a high-speed data link.
The sequence below steps through the process by which photons are converted to datathat can be displayed on a computer monitor. For the sake of simplicity, triggers and gate
pulses are not mentioned and it is assumed that a PCI interface card is installed in thehost computer. When reading through the sequence, keep in mind that electrons are
attracted to more positively charged surfaces and are repelled by more negatively charged
surfaces. This principal is used to control electron flow through the intensifier tube:changing the photocathode voltage with respect to the voltage at the MCP input is used toswitch (gate) the intensifier on and off.
1. Incident photons pass through the intensifier input window, strike the photocathode,and release electrons. (See Figure 2 above.)
2. Assuming that the intensifier is gated ON (the photocathode is more negative than the
MCP input), these electrons will be attracted to the MCP input. Gating acts like a
shutter in that gating the intensifier on allows the CCD to "see" light and gating theintensifier off prevents the CCD from seeing light.
3. Since the voltage at the MCP output is much more positive, most of the electrons
accelerate into the MCP channels and, if they hit the channel walls, will generate* Units having a tapered fiber optic bundle may also be available. Contact the factory for

information.

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additional electrons, resulting in electron gain. The amount of gain is adjusted byincreasing or decreasing the voltage at the MCP output.
4. When the electrons exit the channels they are further accelerated by a constant highvoltage (5-8 kV) and strike the phosphor coating on the fluorescent screen causing it
to release photons. Because of the MCP gain, there are now many photons for eachphoton that struck the photocathode surface.
5. The photons released by the coating are transferred to the surface of the CCD (viafiberoptic or lens), pass through the input window, and produce charge at the pixels
they strike. Note that fiberoptic coupling is not only the most efficient coupling
possible, but lens-coupling effects such as vignetting are eliminated.
6. Charge accumulates in the pixel wells until the intensifier is gated off (thephotocathode is more positive than the MCP input).
7. At that point, the accumulated charge is shifted to the serial register where it is readout to an on-chip amplifier that converts the charge to an analog voltage.
8. This voltage is input to the selected analog-to-digital (A/D) converter where it isdigitally encoded. The conversion speed and the quality of the data are dependent on
the A/D selected (High Speed or Low Noise).
9. The digitized information is transmitted from the camera head through the TAXI
cable to the interface card in the host computer where it is stored in RAM.
10. The application software retrieves the information from RAM, processes it, displays
it, and/or stores it to a file according to user-defined settings.

Safety Information
Safety Related Symbols Used in This Manual
Caution! The use of this symbol on equipment indicates that one ormore nearby items should not be operated without first consulting themanual. The same symbol appears in the manual adjacent to the textthat discusses the hardware item(s) in question.
Caution! Risk of electric shock! The use of this symbol on
equipment indicates that one or more nearby items pose an electric
shock hazard and should be regarded as potentially dangerous. Thissame symbol appears in the manual adjacent to the text that discusses
the hardware item(s) in question.

Chapter 1

Introduction

21

Grounding and Safety
The ST-133 is of Class I category as defined in IEC Publication 348 (Safety
Requirements for Electronic Measuring Apparatus). It is designed for indoor operation
only. Before turning on the controller, the ground prong of the power cord plug must be
properly connected to the ground connector of the wall outlet. The wall outlet must havea third prong, or must be properly connected to an adapter that complies with these safety
requirements.

WARNING! If the equipment is damaged, the protective grounding could be disconnected. Do not use
damaged equipment until its safety has been verified by authorized personnel.
Disconnecting the protective earth terminal, inside or outside the apparatus, or any
tampering with its operation is also prohibited.
Inspect the supplied power cord. If it is not compatible with the power socket, replace thecord with one that has suitable connectors on both ends.

WARNING! Replacement power cords or power plugs must have the same polarity as that of theoriginal ones to avoid hazard due to electrical shock.

Intensifier Modes and Safety
The Experiment Setup Main screen in WinX applications (WinView/32 andWinSpec/32) allows you to select one of three intensifier modes: Shutter Mode, Gate
Mode or Safe Mode. In Shutter Mode operation, the photocathode is biased oncontinuously during the exposure time and the room illumination must be subdued toprevent an overload alarm from occurring. In Gate Mode, the photocathode is biased on
only for the time that each gate pulse is applied. As a result, the tolerance to room light ishigher in gated operation, but the risk of damaging overload from intense light sources
such as lasers remains. In fact, intense light sources in gated experiments can cause spot
damage that would be undetected by the alarm circuit. In Safe Mode, the photocathodeis continuously biased OFF and the intensifier is as safe as it can be.

Audible AlarmTo reduce the risk of camera damage, the PI-MAX camera is equipped with an audible
alarm in the camera head, activated when the intensity of light falling on the image
intensifier exceeds a preset threshold. While the alarm is sounding, the photocathode isdisabled. Immediately switch the MCP On/Off switch on the back of the PI-MAX to the
OFF position. Cover the detector window and only switch the MCP On/Off switch to
ON after the illumination level has been lowered. If the alarm sounds continuously evenwhen the illumination level is adequately low, shut the system down and contact thefactory for guidance.
Note: It is normal for the alarm to sound briefly when the system is turned on.
Caution Discontinue operation and contact the factory at once if sporadic or continuous
unwarranted alarms occur. They may indicate intensifier damage or another situation that
requires immediate attention.

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High Intensity Light Damage
WARNING! Intensified CCD cameras such as the PI-MAX, when biased ON, can be irreparably
damaged if continuously exposed to light levels higher than twice the A/D saturationlevel. Thus it is critical that you not establish conditions that could result in damage tothe intensifier. Although intensified cameras are less prone to damage from backgroundlight when operated gated, they are at significant risk to damage from high-intensity lightsources like a laser. High intensity sources can damage the intensifier before theprotection circuits have time to respond, or even cause spot damage without theprotection circuits acting at all. In Shutter Mode operation, it will be necessary to keep
the lab lighting be subdued when working with an intensified camera. If a sustained
alarm indication occurs when the controller is turned on, immediately switch the MCP
On/Off switch on the back of the PI-MAX to the OFF position. Cover the detector
window and only switch the MCP On/Off switch to ON after the illumination level has
been lowered.
If the alarm sounds continuously even when the illumination level is adequately low, shutthe system down and contact the factory for guidance.

Precautions
To prevent permanently damaging the system, please observe the following precautions:

Always switch off and unplug the ST-133 Controller before changing your system
configuration in any way.

Whenever you turn the ST-133 power OFF, be sure to leave it OFF for at least 30
seconds before switching it back ON. If you switch it ON too soon, a fault logic stateis established that causes the overload alarm to sound continuously.



Never remove the camera’s front window, as it is necessary to maintain vacuum (orto maintain a dry nitrogen environment).



The CCD array is very sensitive to static electricity. Touching the CCD can destroy
it. Operations requiring contact with the device can only be performed at the factory.



Never operate the camera cooled without proper evacuation or backfill. This could
damage the CCD!

Never connect or disconnect any cable while the PI-MAX system is powered on.
Reconnecting a charged cable may damage the CCD.

Never prevent the free flow of air through the equipment by blocking the air vents.

Cleaning and Maintenance
Cleaning the Controller and Camera
Although there is no periodic maintenance that must be performed on the PI-MAX
Camera, users are advised to wipe it down with a clean damp cloth from time to time.
Note: The cloth should be just damp enough to pick up dust – not wet.
This operation should only be done on the external surfaces and with all covers secured.
In dampening the cloth, use clean water only. No soap, solvents or abrasives should beChapter 1

Introduction

23

used. Not only are they not required, but they could damage the finish of the surfaces on
which they are used.

Cleaning Optical Surfaces
Optical surfaces may need to be cleaned due to the accumulation of atmospheric dust. We
advise that the drag-wipe technique be used. This involves dipping a clean cellulose lenstissue into clean anhydrous methanol, and then dragging the dampened tissue over the
optical surface to be cleaned. Do not allow any other material to touch the opticalsurfaces.

Flushing and Refilling the Intensifier Chamber

WARNING!

Under normal conditions the front end of the detector is sealed and backfilled so there isno danger of damage due to condensation.

WARNING!

Operating an Intensified PI-MAX that is no longer backfilled with dry air or dry nitrogenmay result in condensation on the array that could cause irreversible damage. Suchdamage would not be covered by the Warranty.
Before a PI-MAX camera leaves the factory, its front enclosure is backfilled with clean
dry air or, in the case of the sealed-nose IVUV detector, only dry nitrogen. For proper
operation it is essential that the integrity of the front enclosure be maintained. NEVER
remove the window from in front of the intensifier or loosen the backfill port screw (seepage 199). If this enclosure should be opened to the air, the array and intensifier will be
exposed to atmospheric moisture, which could condense on the array as it cools andpossibly cause irreversible damage.
In normal operation, the front enclosure should remain sealed for the life of the detector
and should require no maintenance to assure integrity. If it should ever happen that thefront enclosure becomes unsealed, contact the factory and arrange to return the detector
to the factory where it can be properly flushed, backfilled and resealed again. See
page 232 for contact information.

Repairs
Save the original packing materials. Because the PI-MAX system contains no userserviceable parts, repairs must be done by Princeton Instruments. Should your systemneed repair, contact Princeton Instruments customer support for instructions (telephone,e-mail, and address information are provided on page 232 of this manual).
Use the original packing materials whenever shipping the system or system components.

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Manual Organization
This manual provides the user with all the information needed to install a PI-MAX
Intensified CCD camera and place it in operation. Topics covered include a detailed
description of the camera, installation and setup, first time data acquisition, tips andtricks, microscopy applications, temperature control and more. A brief description ofeach of the chapters follows.
Notes:
1. The general identifier "ST-133" is used for both the ST-133A Controller and theST-133B Controller. Where there is a difference, the specific identifier is used.
2. "WinX" is a generic term for WinView/32, WinSpec/32, and WinXTest application
software.
Chapter 1, Introduction provides an overview of the PI-MAX camera. Topics
include a description, theory of operation, and specifications.
Chapter 2, Installation Overview cross-references system setup actions with therelevant manuals and/or manual pages. It also contains system layout diagrams.
Chapter 3, System Setup provides detailed directions for installing and setting up
the PI-MAX for both spectroscopy and imaging.
Chapter 4, First Light provides abbreviated directions for getting your PI-MAX
into operation as soon as possible.
Chapter 5, General Operation Factors provides information about experiment
setup, temperature control, background subtraction, array readout, binning, anddigitization. These are factors that should be considered whether you are setting
an experiment in shutter or gate mode.
Chapter 6, Shutter Mode Operation discusses issues specific to operating the
PI-MAX system in shutter mode.
Chapter 7, Gated Operation with a PTG discusses issues specific to operating
the PI-MAX system in gate mode with an installed PTG.
Chapter 8, Gated Operation with a DG535 discusses issues specific tooperating the PI-MAX system in gate mode with a Stanford Research DG535.
Chapter 9, Kinetics Operation describes the Kinetics option and includes
example experiments.
Chapter 10, PI-MAX2 DIF Camera describes the operation of the PI-MAX2 DIF
system.
Chapter 11, Tips and Tricks discusses a number of issues that can have a bearing
on getting good experimental results.
Chapter 12, Microscopy Applications discusses how to mount the PI-MAX
camera to a microscope. Includes discussion of various adapters, focusing
considerations and sensitivity to damage from EMF spikes generated by Xenon
or Hg arc lamps.
Chapter 13, TTL Control discusses the purpose and operation of the TTL In/Out
Function.

Chapter 1

Introduction

25

Chapter 14, System Component Descriptions describes the PI-MAX Camera,
the ST-133, and other system components. Includes descriptions of connectors
and other front and rear panel features.
Chapter 15, Troubleshooting provides information regarding possible systemproblems.
Appendix A, Specifications provides general specifications as well as operating
environment and internal pulser specifications.
Appendix B, Outline Drawings includes outline drawings for the ST-133A
Controller, the ST-133B Controller, and the PI-MAX camera.
Appendix C, Software explains how the PI-MAX camera is controlled using the
WinX application software.
Appendix D, C-Mount and F-Mount Adapters provides information on the
C-Mount and F-Mount adapters available for the PI-MAX Camera. Also includes
a discussion of lens focusing.
Appendix E, Spectroscopy-Mount and Spectrograph Adapters provides
mounting instructions for the spectroscopy-mount adapter and for the
spectrograph adapters available for PI-MAX cameras with spectroscopy-mounts.
Appendix F, IVUV Detector discusses the purge requirements of the IVUV
variant of the PI-MAX.
Appendix G, USB 2.0 Limitations covers the currently known limitations
associated with operating under the USB 2.0 interface.
Appendix H, Glossary provides definitions of commonly used words and terms
related to intensified camera characteristics and usage.
Declarations of Conformity contains the Declarations of Conformity for PI-MAX
systems.
Warranty & Service details the warranties for Princeton Instruments equipment
and software.

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Chapter 2
Installation Overview
The list and diagrams below briefly describe the sequence of actions required to
install your system and prepare to gather data. Refer to the indicated references
for detailed information.
ActionReference

1. If the system components have not already been unpacked, unpackthem and inspect their carton(s) and the system components for intransit damage.

Chapter 3 System Setup,
page 33

2. Verify that all system components have been received.

Chapter 3 System Setup,
page 33

3. If the components show no signs of damage, verify that theappropriate voltage settings have been selected for the Controller.

Chapter 3 System Setup,
page 36

4. If the Camera will be used on a spectrograph or microscope, mountit to the equipment using the required adapter(s).

Spectroscopy: Appendix E,
page 203
Microscopy: Chapter 12,
page 143

5. If the application software is not already installed in the hostcomputer, install it.

Application manual.

6. If the appropriate interface card is not already installed in the hostcomputer, install it.

Chapter 3 System Setup,
page 38

7. With the Controller and computer power turned OFF, connect theinterface cable (TAXI or USB) to the Controller and the interface
card in the host computer. Then tighten down the locking hardware.

Chapter 3 System Setup,
page 42 (TAXI) or
page 42 (USB 2.0)

8. With the Controller power turned OFF, connect the DetectorController cable(s) to the appropriate connector(s) on the rear of theController. Adjust the slide latches so the cable connection islocked or tighten down the locking hardware, as appropriate.

Chapter 3 System Setup,
page 42

9. With the Controller power turned OFF, connect the DetectorController cable(s) to the appropriate connector(s) on the rear of the
Camera. Then tighten down the locking hardware.

Chapter 3 System Setup,
page 42

Chapter 15 Troubleshooting,page 181

10. With the Controller power turned OFF, connect the Controller
power cord to the rear of the controller and to the power source.
11. With the Controller power turned OFF, make the cable connections
to the PTG or the DG535 Timing Generator.

Chapter 3 System Setup,
page 43

12. If the system is cooled by coolant circulation, make the tubing
connections between the coolant circulator and the Camera.

Chapter 3 System Setup,
page 4427

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ActionReference

14. Turn on the computer and begin running the WinX application.
When the computer boots, you may be asked for the location of theinterface drivers. If this is the first time you have used a WinX
application, the Camera Detection wizard will automatically run.
This wizard retrieves information from the camera and/or ST-133
and enters this information as the default parameters for yoursystem.

Chapter 3 System Setup,
page 38 (PCI drivers),
page 40 (USB drivers),
page 44 (Camera Detection
Wizard)15. Verify the hardware setup information or change the parameters, as
appropriate. Enter the pulser information. Enter the experiment setup
parameters. If using a spectrograph, enter that setup information

WinView/32 or
WinSpec/32 manual

16. Set the target array temperature.

Setting the Temperature,
page 58

17. When the system reaches temperature lock, wait an additional 20
minutes and then begin acquiring data in focus mode.

Initial Data Acquisition,
page 51

18. Adjust the focus for the best image or spectral lines. If you are using
WinSpec/32, you may want to use the Focus Helper function for thispurpose.

Appendix D C-Mount andF-Mount Adapters,
page 201
Appendix E SpectroscopyMount and Spectrograph
Adapters, page 204

13. Turn the Controller ON.

WinView/32 or
WinSpec/32 manual

Configuring the Software
for Shutter Mode
Operation, page 49

Chapter 2

Installation Overview

Figure 3. PI-MAX with PTG System Diagram

Figure 4. PI-MAX2 with PTG System Diagram

29

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Figure 5. Gen II PI-MAX with DG535 System Diagram

Figure 6. Gen II PI-MAX2 with DG535 System Diagram

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Chapter 2

Installation Overview

Figure 7. Gen III PI-MAX with DG535 System Diagram

Figure 8. Gen III PI-MAX2 with DG535 System Diagram

31

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Chapter 3
System Setup
Introduction
This chapter includes general instructions for setting up a PI-MAX system for operationin both imaging and spectroscopic applications. For microscopy applications, also see
Chapter 12, Microscopy Applications.

Dangers and Warnings
DANGER

Voltages inside the PI-MAX may exceed 6,000 volts. To avoid possible hazard to
personnel, use the instrument only according to the directions in this manual and only forthe purposes for which it is designed. Never attempt to operate the PI-MAX with its
covers removed.

WARNING Image intensified detectors can be destroyed if exposed to excessive light levels.
Princeton Instruments cannot take responsibility for PI-MAX detector damage due tomisuse. Intensified cameras are particularly susceptible to overload damage when
operated in conjunction with high-intensity light sources such as lasers. Spot damage canoccur without the overload condition being detected.
The PI-MAX has an audible alarm and shutdown circuit to bias the photocathode OFF if
excessive photocathode current is detected. The circuit automatically resets and biases thephotocathode back on after about 0.5 seconds. The short-term protection provided will
not prevent intensifier damage if excessive light is allowed to continuously fall on theintensifier. It is also possible for excessively bright spots to damage the intensifier tube
without triggering the alarm.

Unpacking the System
During unpacking, check the system components for possible signs of shipping damage.
If there are any, notify Princeton Instruments and file a claim with the carrier. Be sure tosave the shipping carton for inspection by the carrier. If damage is not apparent but
system specifications cannot be achieved, internal damage may have occurred in
shipment. Please save the original packing materials so you can safely ship the camera
system to another location or return it to Princeton Instruments for repairs if necessary.

Checking the Equipment and Parts Inventory
Confirm that you have all of the equipment and parts required to set up the PI-MAX
system. A typical system consists of:PI-MAX camera (Gen II or Gen III).



ST-133 Controller.
33

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PI-MAX/PI-MAX2 System Manual

Version 5.GTiming Generator: a PTG (installed in the ST-133) or a Stanford Research
Systems DG535 Digital Delay/Pulse Generator with Inhibit Option and GPIB
cables.*

Detector-Controller cable:


PI-MAX: DB25 to DB25 cable. Standard length is 15 ft (6050-0336).

PI-MAX2: Cable set, 15 ft (6050-0499)

Computer Interface: TAXI or USB 2.0.

Computer: Can be purchased from Princeton Instruments or provided by user.

WinView/WinSpec CD-ROM

User Manuals

Interface Dependent Components:Controller-Computer Interface cable:

TAXI cable: DB9 to DB9 cable (6050-0148-CE is standard) orUSB cable: Five (5) meter cable (6050-0494) is standard

Interface Card: High Speed PCI Interface board for TAXI interface. USB 2.0
board for USB 2.0 interface is user-provided: native USB 2.0 support on themotherboard or USB 2.0 Interface Card (Orange Micro 70USB90011
USB 2.0 PCI is recommended for desktop; SIIG, Inc. USB 2.0 PC Card,
Model US2246 for laptop).

System Dependent Components
PI-MAX to DG535 cable (6050-0385) and Filter (2550-0347)

PI-MAX to PTG cable: Custom DB9 to DB9 cable (6050-0406, 15 ft/5 m isstandard)



GPIB cables if a DG535 has been ordered Coolant Circulator and Coolant Tubing
If there are any problems, contact the Princeton Instruments Customer Support
department (see page 232 for contact information).

System Requirements
Environmental

Storage temperature 55°C
Operating environment temperature: 30°C > T > -25°C
Relative humidity <50% noncondensing...

Ventilation
Camera: Allow at least one-inch clearance for side and rear air vents.

* Contact factory for information on how to install/enable the DG535 Inhibit function.

Chapter 3

System Setup

35

ST-133: There is an internal fan located at the right side of the rear panel behind an
exhaust opening. Its purpose is simply to cool the controller electronics. This fanruns continuously whenever the controller is powered. Air enters the unit throughventilation openings on the side panels, flows past the warm electronic
components as it rises, and is drawn out the rear of the controller by the fan. It is
important that there be an adequate airflow for proper functioning. As long as
both the controller’s intake ventilation openings and the fan exhaust opening
aren’t obstructed, the controller will remain quite cool.

Power
Camera: The PI-MAX camera receives its power from the ST-133, which in turn plugs
into a source of AC power.
ST-133: The ST-133 Controller can operate from any one of four different nominal line
voltages: 100, 120, 220, or 240 V AC. Refer to the Fuse/Voltage label on theback of the ST-133 for fuse, voltage, and power consumption information.
The plug on the power cord supplied with the system should be compatible withthe line-voltage outlets in common use in the region to which the system isshipped. If the power cord plug is incompatible, a compatible plug should beinstalled, taking care to maintain the proper polarity to protect the equipment andassure user safety.
Caution

Whenever you turn the ST-133 power OFF, be sure to leave it OFF for at least 30
seconds before switching it back ON. If you switch it ON too soon, a fault logic
state is established that causes the overload alarm to sound continuously.

Host Computer
Note: Computers and operating systems all undergo frequent revision. The following
information is only intended to give an approximate indication of the computerrequirements. Please contact the factory to determine your specific needs.
Requirements for the host computer depend on the type of interface, TAXI or USB 2.0,
that will be used for communication between the ST-133 and the host computer. Thoserequirements are a listed below according to protocol.
TAXI Protocol:AT-compatible computer with 200 MHz Pentium® II (or better).



Windows® XP (32-bit, SP3 or later) or Vista (32-bit) operating system.



High speed PCI serial card (or an unused PCI card slot). Computers purchasedfrom Princeton Instruments are shipped with the PCI card installed if High speed
PCI was ordered.



Minimum of 32 Mbytes of RAM for CCDs up to 1.4 million pixels. Collecting
multiple spectra at full frame or high speed may require 128 Mbytes or more ofRAM.

CD-ROM drive.

Hard disk with a minimum of 80 Mbytes available. A complete installation of the
program files takes about 17 Mbytes and the remainder is required for data
storage, depending on the number and size of spectra collected. Disk levelcompression programs are not recommended.

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Version 5.GSuper VGA monitor and graphics card supporting at least 256 colors with at least
1 Mbyte of memory. Memory requirement is dependent on desired display
resolution.

IEEE-488 GPIB port (required by DG535 Timing Generator, if present). May
also be required by Spectrograph.



Two-button Microsoft® compatible serial mouse or Logitech three-button
serial/bus mouse.
USB 2.0 Protocol:AT-compatible computer with Pentium 3 or better processor and runs at 1 GHz or
better.



Windows® XP (32-bit, SP3 or later) or Vista® (32-bit).



Native USB 2.0 support on the mother board or USB Interface Card (Orange
Micro 70USB90011 USB 2.0 PCI is recommended for desktop; SIIG, Inc. USB
2.0 PC Card, Model US2246 for laptop)

Minimum of 256 Mb of RAM.



CD-ROM drive.

Hard disk with a minimum of 80 Mbytes available. A complete installation of the
program files takes about 17 Mbytes and the remainder is required for data
storage, depending on the number and size of spectra collected. Disk levelcompression programs are not recommended.

Super VGA monitor and graphics card supporting at least 256 colors with at least
1 Mbyte of memory. Memory requirement is dependent on desired display
resolution.

IEEE-488 GPIB port (required by DG535 Timing Generator, if present). May
also be required by Spectrograph.



Two-button Microsoft compatible serial mouse or Logitech three-button
serial/bus mouse.

Verifying Controller Voltage Setting
The ST-133’s power requirements are discussed in Appendix A.
Note that the PI-MAX power requirements are entirely provided
by the ST-133 via the Detector-Controller cable.
The Power Module on the rear of the Controller contains thevoltage selector drum, fuses and the power cord connector. The
appropriate voltage setting is set at the factory and can be seen on
the back of the power module. Each setting actually defines arange and the setting that is closest to the actual line voltage
should have been selected. The correct fuses for the country
where the ST-133 is to be shipped are installed at the factory.

Figure 9. Power
ModuleNote: On ST-133s, the voltage ranges and fuse ratings may be printed above or below
the power module.

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To Check the Controller's Voltage Setting:
1. Look at the lower righthand corner on the rear of the Controller. The current
voltage setting (100, 120, 220, or 240 VAC) is displayed on the Power Module.
2. If the setting is correct, continue with the installation. If it is not correct, follow
the instructions on page 168 for changing the voltage setting and fuses.

Mounting the PI-MAX
Imaging Applications
The PI-MAX is supplied with the lens mount specified when the system was ordered,normally either a screw-type C-mount lens or a bayonet type F-mount lens, allowing a lensof the corresponding type to be mounted quickly and easily. The installed mount is securedby three setscrews, which must be loosened to remove it. Appendix D illustrates the mounts
and also discusses focusing.
The PI-MAX can be mounted at any attitude or angle. The camera can rest on any securesurface. Take care not to block the ventilation openings.

WARNING In the case of cameras equipped with F-mount, do not mount the camera in the nose-up
operation where the lens mount would be required to hold the camera’s weight. The
F-mount is not designed to sustain the weight of the camera in this orientation and thecamera could pull free. You must provide additional support for the camera.

Should the camera be mounted in the nose-up position beneath a table, take care toprotect the mounting components from lateral stresses, such as might occur should
someone accidentally bump the camera with a knee while working at the table. One
solution to this problem would be to install a barrier between the camera and operator toprevent any accidental contact.
There are no special constraints on nose-down operation. Again, however, good operating
practice might make it advisable to take steps to prevent accidental contact from unduly
stressing the mounting components.

WARNING Always begin with the lens stopped all the way down (largest f/ stop number) tominimize the risk of overloading the intensifier.

Spectroscopy Applications
The PI-MAX detector must be properly mounted to the spectrograph to achieve thehighest resolution. In the correct orientation, the text on the back of the detector shouldbe right side up. Take care not to block the ventilation openings. Refer to Appendix E forspectrograph adapter mounting instructions.

Microscopy Applications
If the camera is going to be mounted to a microscope, refer to Chapter 12 for mounting
instructions and other information relating to microscopy applications. Many standard
microscope adapters are available through Princeton Instruments.

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Installing the Application Software
Installation is performed via the
WinX installation process. If you
are installing WinView/32 or
WinSpec/32 for the first time andhave a TAXI interface, you should
run the installation before the PCIinterface card is installed in the hostcomputer. On the SelectComponents dialog (see Figure10), click on the AUTO PCI button
to install the interface card drivers(PCI and the Princeton Instruments
USB drivers) and the mostcommonly installed program files.
Figure 10. WinView/32 Installation: Interface Card
Select the Custom button if you
Driver Selection
would like to choose among theavailable program files or do not want to install the PCI driver.
Note: WinView/32 and WinSpec/32 (versions 2.6.0 and higher) do not support the ISA
interface.

Setting up the Communication Interface
PI-MAX and PI-MAX2 camera systems require either an installed Princeton Instruments(RSPI) PCI card or an installed USB2.0 interface card in the host computer. The type ofinterface card is dictated by the Interface Control Module installed in the ST-133
controller.

Setting up a PCI Interface
Administrator privileges are required under Windows® XP, and Window Vista® toinstall software and hardware.
A PCI card must be installed in the host computer if the communication
between computer and controller uses the TAXI protocol (i.e., theInterface Control Module installed in the ST-133 has a 9-pin
SERIAL COM connector as shown in the figure at right). With TAXI
protocol, the standard cable provided with an ST-133 is 7.6 meters(25 feet) (cable lengths up to 50 meters are available) and thedigitization rate may be as high as 5 MHz.
A computer purchased from Princeton Instruments will be shipped with
the PCI card already installed. Otherwise, a PCI card will be shippedwith the system and you will have to install it in the host computer atyour location.
Note: The PCI card can be installed and operated in any Macintosh®
having a PCI bus, allowing the ST-133 to be controlled from theMacintosh via IPLab™ software and the PI Extension.

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Caution If you are using the WinX application software, either High Speed PCIor PCI(Timer) can be the selected Interface type. This selection isaccessed on the Hardware Setup| Interface tab. High Speed PCI
allows data transfer to be interrupt-driven and gives the highest
performance in some situations. PCI(Timer) allows data transfer to becontrolled by a polling timer. This selection is recommended when there
are multiple devices sharing the same interrupt.
To Install a PCI Serial Buffer Card in the Host Computer:
1. Review the documentation for your computer and PCI card before continuingwith this installation.
2. To avoid risk of dangerous electrical shock and damage to the computer, verify
that the computer power is OFF.
3. Remove the computer cover and verify that there is an available PCI slot.
4. Install the PCI card in the slot.
5. Make sure that the card is firmly seated and secure it.

6. Replace and secure the computer cover and turn on the computer only. If an error
occurs at bootup, either the PCI card was not installed properly or there is anaddress or interrupt conflict. Refer to Chapter 15 "Troubleshooting", page 165 for
instructions.
Note: The PCI card has no user-changeable jumpers or switches.
To Install the PCI Card Driver
The following information assumes that you have already installed the WinX application
software (WinView/32, WinSpec/32, or WinXTest).
1. After you have secured the PCI card in the computer and replaced the cover, turnthe computer on.
2. At bootup, Windows will try to install the new hardware. If it cannot locate thedriver, you will be prompted to enter the directory path, either by keyboard entry
or by using the browse function.
If you selected AUTO PCI during the application software installation, the required
INF file is automatically copied into the Windows\Inf directory and the PCI card
driver file is copied into the Windows\System32\ Drivers directory. Refer to Table 1
for the appropriate file names and locations.
Windows Version

PCI Inf Filename
Located in "Windows"\Infdirectory*

PCI Device Driver Name
Located in "Windows"\System32\Drivers
directory

Windows® XP andWindows Vista®
(32-bit)rspi.inf (in Windows\inf, forexample)rspipci.sys (in Windows\System32\drivers,
for example)* The Inf directory may be hidden.
Table 1. PCI Driver Files and Locations

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Setting up a USB 2.0 Interface
Administrator privileges are required under Windows® XP and Windows Vista®
(32-bit) to install software and hardware.
Your system has been configured to use the USB communication protocol if theInterface Control Module installed in the ST-133 has a USB 2.0 connector as shownin the figure at right). The advantages to the USB 2.0 interface are that it uses a muchhigher data transfer rate than many common serial data formats (such as the TAXI
protocol) and it simplifies the connection to external devices. USB supports "plug andplay" -- you do not need to be heavily involved in the setup process.
USB 2.0 Limitations
 Maximum cable length is 5 meters (16.4 feet) 1 MHz is currently the upper digitization rate limit for the ST-133 Controller.
Large data sets and/or long acquisition times may be subject to data overrun
because of host computer interrupts during data acquisition.
USB 2.0 is not supported by the Princeton Instruments PC Interface Library (EZDLLS).



Some WinX (WinView/32 and WinSpec/32) 2.5.X features are not fully
supported with USB 2.0. Refer to Appendix G, page 217, for more information.

Note: If you are installing the USB 2.0 interface on a laptop, you will need to perform allof the operations described in this section. In addition, if you are using the recommended
USB Interface Card (SIIG, Inc. USB 2.0 PC Card, Model US2246), you must replace theOrangeUSB USB 2.0 Host Controller driver installed for that card with the appropriate
Microsoft driver. Instructions for making the replacement are included in "To Update theOrangeUSB USB 2.0 Driver".
To Update the OrangeUSB USB 2.0 Driver:This procedure is highly recommended when a laptop computer will be used tocommunicate with the ST-133. As stated before, we recommend the SIIG, Inc. USB 2.0
PC Card, Model US2246 if USB 2.0 is not native to the laptop's motherboard. To reducethe instances of data overruns and serial violations, the OrangeUSB USB 2.0 Host
Controller installed for the SIIG card, should be replaced by the appropriate Microsoft
driver (Windows XP or Vista (32-bit), depending on the laptop's operating system.)
Note: This procedure may also be performed for desktop computers that use the Orange
Micro 70USB90011 USB 2.0 PCI.
1. Download and install Microsoft Service Pack Pack 3 (for Windows XP) if theservice pack has not been installed.
2. From the Windows Start menu, select Settings|Control Panel.
3.

Select System and then System Properties.

4.

Select the Hardware tab and click on Device Manager button.

5. Expand Universal Serial Bus Controllers.
6. Right-mouse click on OrangeUSB USB 2.0 Host Controller and selectProperties.

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7. On the Driver tab, click on the Update Driver… button. You may have to
wait a minute or so before you will be allowed to click on the button.
8. When the Upgrade Device Driver Wizard appears, click on Next. Select the
Search for a suitable driver … radio button.
9. On the next screen select the Specify a location checkbox.
10. Browse and select the location. Click on OK.
11. In the Driver Files Search Results window, check the Install one of theother drivers check box.
12. Select the NEC PCI to USB Enhanced Host Controller B1 driver. Click on
Next and the installation will take place. When the Completing the Upgrade
Device Driver Wizard window appears, click on Finish. You will then be
given the choice of restarting the computer now or later. According to thewindow text, the hardware associated with the driver will not work until you
restart the computer.
To Install the Princeton Instruments USB 2 Interface:
The following information assumes that: You have verified that the host computer meets the required specifications
for USB 2.0 communication with the PI-MAX or PI-MAX2 system (seepage 35).
 A USB 2.0 board and its driver are installed in the host computer.
 The ST-133 has an installed USB 2.0 Interface Control module.
 You have already installed the WinX application software (versions 2.5.15
and higher). Versions 2.5.15 and higher automatically install the driver and
INF files required to support the USB 2.0 Interface Control module.
1. Before installing the Princeton Instruments USB2 Interface, we recommendthat you defragment the host computer's hard disk. This operation reduces thetime the computer spends locating files. Typically, the "defrag" utility "Disk
Defragmenter" can be accessed from the Windows® Start menu and canusually accessed from the Programs/Accessories/System Tools subdirectory.
2. After defragmenting the hard disk, turn off the computer and make the USB
cable connections between the host computer and the ST-133. Then, turn the
ST-133 on before turning on the host computer.
3. At bootup, Windows will detect the Princeton Instruments USB 2 Interface
hardware (i.e., the USB 2.0 Interface Control module). You may be prompted
to enter the directory path(s) for the apausbprop.dll and/or the apausb.sys
file(s), either by keyboard entry or by using the browse function. If you
selected AUTO PCI during the application software installation, the required
INF file is automatically copied into the Windows\Inf directory and the USB
driver file is copied into the "Windows"\System32\ Drivers directory. Refer toTable 2 for the appropriate file names and locations.

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USB Inf Filename
USB Device Driver Name
Located in "Windows"\Inf Located indirectory*"Windows"\System32\Drivers directory

Windows® XP and rspi.inf (in Windows\inf,Windows Vista®
for example)(32-bit)rspipci.sys (in Windows\System32\drivers,
for example)* The Inf directory may be hidden.
Table 2. USB Driver Files and Locations

Connecting the Interface (Controller-Computer) Cable
TAXI® Cable (6050-0148-CE)
Caution Turn the Controller power OFF (OFF = 0, ON = |) before connecting or
disconnecting the Detector-Controller cable.
To Connect the TAXI Cable:
1. Verify that the Controller power is OFF.
2. Verify that the Computer power is OFF.
3. Connect one end of the TAXI cable to the 9-pin port on the Interface card in thehost computer.
4. Tighten down the screws to lock the connector in place.
5. Connect the other end to the "Serial Com" port on the rear of the Controller.
6. Tighten down the screws to lock the connector in place.

USB 2.0 Cable (6050-0494)
Caution Turn the Controller power OFF (OFF = 0, ON = |) before connecting or
disconnecting the Detector-Controller cable.
To Connect the USB 2.0 Cable:
1. Verify that the Controller is OFF.
2. Verify that the Computer power is OFF.
3. Connect one end of the USB cable to the USB port on the host computer.
4. Connect the other end to the USB 2.0 port on the rear of the Controller.

Connecting the Detector-Controller Cable
Caution Turn the Controller power OFF (OFF = 0, ON = |) before connecting or
disconnecting the Detector-Controller cable.
To Connect the Detector-Controller Cable:
1. Verify that the Controller is OFF.
2. Connect the Detector-Controller cable to the Controller.
PI-MAX: Connect the male end of the cable to the "Detector" port on the Controller.
Refer to "Securing the Detector-Controller Cable Slide Latch", page 181.
PI-MAX2: Connect the male ends of the cable set the "Camera Signal" and"Camera Pwr" ports on the Controller.

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3. Lock the connector(s) in place.
4. Connect the Detector-Controller cable to the camera.
PI-MAX: Connect the female end of the cable to the "Power/Signal" port on thecamera.
PI-MAX2: Connect the female ends of the cable set to the "Signal" and "Power"
ports on the camera.
5. Lock the connectors in place.

Connecting to the Timing Generator
PTG
1. Verify that the Controller power is OFF.
2. If you are planning to operate in Gate Mode (see Chapter 7 for more
information), connect the PI-MAX to PTG cable (6050-0406) to the Timing
Gen connector on the PTG board and to the Timing Gen connector on the backof the PI-MAX. Secure the cable with the locking hardware provided.
3. If you are using an external signal to trigger the gate timing sequence, use a BNC
cable to connect the signal source to the Ext. Trig. In connector on the PTG.

DG535
1. Verify that the Controller power is OFF.
2. Connect the Filter (2550-0347) to the Timing Gen connector on the back of the
PI-MAX and secure the locking hardware.
3. Connect the PI-MAX to DG535 cable (6050-0385) to the Filter on the back of
the PI-MAX and secure the locking hardware. The cable branches into three
BNC cables, which connect as follows.


The A Start cable connects to the DG535 A BNC output.



The B Stop cable connects to the DG535 B BNC output.



Gen II Intensifier: Connect the C+D-Gen II/A+B-Gen III cable to the
DG535
output if the PI-MAX has a Gen II intensifier and you plan
to do bracket pulsing. Leave the cable disconnected if you plan to operate in
Shutter Mode or will not be bracket pulsing.

Gen III Intensifier: Connect the C+D-Gen II/A+B-Gen III cable to the
DG535
output if the PI-MAX has a Gen III Intensifier.

4. Connect the DG535-to-Computer GPIB cable (6050-0170) from the IEEE-488
GPIB Std Port connector on the back of the DG535 to the interface connectorof the computer’s IEEE-488 Interface card.
5. Connect a BNC cable from the ST-133’s Ext. Sync input to the DG535’s BNC
D output.
6. Connect a BNC cable from the Controller’sconnector to the Inhibit
input of the DG535 (The DG535 must be equipped with the Inhibit option). Thisconnection serves to prevent the DG535 from sending triggers while the array is
being read out.

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Making the Coolant Circulator-Camera Connections
PI-MAX2 cameras do not use supplemental water cooling. However, PI-MAX cameras
have two coolant ports on the back panel for connection to a coolant circulator. The two
ports are identical; it does not matter which is used for inflow and which for outflow.
Caution

1. Do not use any coolant fittings other than those supplied by Princeton Instruments.
Although standard pipefittings are similar, in most cases they are not the same.
Forcing these fittings into the cooling block will permanently damage the threads.
2. Coolant should be no colder than +15°C to prevent condensation at 50% relative
humidity. Operating a PI-MAX camera with coolant at a colder temperature could
cause induced condensation in the electronics enclosure and possible catastrophic
damage to the camera. Damage resulting from this type of operation will void thewarranty.
3. Coolant can be water or it can be a 50:50 mixture of ethylene glycol and water, if thecoolant temperature is below the freezing point for water.
4. Take care that the coolant used is pH neutral. Acidic or alkaline coolant can damage
the camera fittings and internal cooling block through corrosion. Such damage could
be very expensive to repair.
1. Set up the coolant circulator according to the directions in the user manual for that
equipment. Do not apply power to the circulator until directed to do so.
2. Using 1/4", thin-wall plastic tubing, make the hose connections between the water portson the rear of the camera to the ports on the coolant circulator. The two water ports are
identical so either can be used for inflow. For best cooling performance, the tubing
should be no longer than necessary.
3. Using suitable clamps, secure the tubing at both ends. Barb-sleeve clamps (PI partnumber 2518-0301) are provided. Make the hose connections between the circulator
and the camera.
Recommended Flow Rate and Fluid Pressure
Flow Rate: > 1 liter/minute. Users are advised to install a flow meter to monitor
the rate.
Fluid Pressure: 25 psig (maximum).

Entering the Default Camera System Parameters into WinX
(WinView/32, WinSpec/32, or WinXTest/32)
Software changes implemented in WinX version 2.15.9.6 affected the way in which
default parameters were entered for camera systems. Therefore, two sets of instructions
are included. Follow the instructions appropriate to the software version that you
installed. Note that these instructions assume that you have performed the computerinterface installation.
WinX Versions 2.5.19.6 and later
1. Make sure the ST-133 is connected to the host computer and that it is turned ON.

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2. Run the WinX application. The Camera Detection wizard will automatically run if
this is the first time you have installed a Princeton Instruments WinX application(WinView/32, WinSpec/32, or WinXTest/32) and a supported camera. Otherwise, if
you installing a new camera type, click on the Launch Camera Detection
Wizard… button on the Controller/CCD tab to start the wizard.
3. On the Welcome dialog (Figure 11), leave the checkbox unselected and click on
Next.

Figure 11. Camera Detection Wizard - Welcome dialog

4. Follow the instructions on the dialogs to perform the initial hardware setup: thiswizard enters default parameters on the Hardware Setup dialog tabs and gives you an
opportunity to acquire a test image to confirm the system is working.
WinX Versions before 2.5.19.6
1. Make sure the ST-133 is connected to the camera and the host computer and that it isturned on.
2. For ST-133s containing a TAXI Interface module, go to Step 5.
3. For ST-133s containing a USB 2.0 Interface module, run RSConfig from theWindows|Start|Programs|PI Acton menu or from the directory where you
installed the WinX application (WinView/32, WinSpec/32, or WinXTest).
4. When the RSConfig dialog (Figure 12) appears, you can change the camera nameto one that is more specific or you can keep the default name "Camera1". Whenyou have finished, click on the Done button.
Note: If the first camera in the list is not the "Princeton Style (USB2)", you willneed to edit the PVCAM.INI file created by RSConfig. See the instructions in"Demo, High Speed PCI, and PCI(Timer) are Choices on Hardware
Wizard:Interface dialog (Versions 2.5.19.0 and earlier)", page 172.

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Figure 12. RSConfig dialog

5. Open the WinX application and, from Setup|Hardware…, run the Hardware
Setup wizard and make the appropriate selections for your system. After the
wizard is finished, the Controller/Camera tab card will be displayed.
Note: If your system is using the USB 2.0 interface, click the Yes radio button
if the PVCAM dialog (Figure 13) is displayed. Otherwise, click No and continue
through the wizard.

Figure 13. Hardware Setup wizard: PVCAM dialog

6. You should now be able to set up experiments and acquire data. Run the software
in focus mode to verify communication between the ST-133 and the hostcomputer.

Chapter 4First Light
Introduction
This chapter contains procedures (imaging and spectroscopy) that you can use to verify
PI-MAX system operation. To reduce the complexity of the setup (hardware andsoftware), these procedures are run in Shutter Mode. Much of the setup can be
performed under normal lighting. However, the risk of overloading the camera in thismode demands that you subdue room or ambient illumination to where it is hard to see
with the eye before data acquisition is started.
Procedures for operating in Gate mode are included in the Gate Mode Operation chaptersfor the PTG and the DG535.
Note: Issues that could be of importance in some applications are omitted in this chapter
for the sake of brevity. General application issues are addressed in Chapter 6 and thosethat are specific to Shutter Mode and to Gate Mode are addressed in the appropriate
chapters.

Required Equipment and Cables
The equipment and cables listed below are required to set up and run the PI-MAX camera
system in accordance with the procedures in this chapter. Additional equipment andcables required for Gate mode operation and for timing modes other than Free Run
are not included in this list.
Princeton Instruments PI-MAX CameraPrinceton Instruments ST-133 Controller.



PC equipped with a Princeton Instruments (RSPI) PCI Interface card.



Cables: PI-MAX to Controller: 6050-0336 for standard PI-MAX or 6050-0499 cable set
for PI-MAX2
 TAXI high-speed serial data: 6050-0148 CE

The system may also include a spectrograph. If so, the camera must be properly
mounted to it as described in the spectrograph manual. If the spectrograph will becomputer-controlled, a suitable interface cable will additionally be required. See
Appendix E "Spectroscopy-Mount and Spectrograph Adapters", starting on
page 203.

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Cable Connections
WARNING! All of the system components must be
turned off before connecting or disconnecting cables.
The following cabling configuration is used when operating in Shutter Mode. If thesystem includes a spectrograph, see your spectrograph manual for information on the
spectrograph’s cabling requirements.
1. Connect the PI-MAX to Controller cable.


PI-MAX: Connect cable 6050-0336 from the Power/Signal connector on theback of the PI-MAX to the Detector connector on the back of the Controller.



PI-MAX2: Connect cable set 6050-0449 as follows. Connect cable 6050-0492
from the Signal connector on the back of the PI-MAX2 to the Camera Signal
connector on the back of the Controller. Connect cable 6050-0493 from thePower connector on the back of the PI-MAX2 to the Camera Pwr connector on
the back of the Controller.
2. Connect the Controller-to-Computer Interface cable.


PI-MAX: For standard PI-MAX systems, the Controller-to-Computer interface
type is determined by the Interface card (TAXI or USB 2) installed in theController.


TAXI Interface: Connect serial data cable (6050-0148 CE) from the ST-133
SERIAL COM connector to the computer’s Princeton Instrument (RSPI) PCI
Serial Interface card connector.

USB 2 Interface: Connect the USB cable (6050-0494) from the ST-133
USB 2.0 connector to the computer's USB 2.0 Interface card connector.

PI-MAX2: PI-MAX2 systems use the TAXI communication protocol. Connect
the TAXI serial data cable (6050-0148 CE) from the ST-133 SERIAL COM
connector to the computer’s Princeton Instruments (RSPI) PCI card connector.
3. If the system includes a PTG, no other cable connections are required for operating in
Shutter Mode. Procedures for operating with a PTG or a DG535 in Gate Mode areincluded in the appropriate Gated Operation chapter.

Before Turning on the System
1. Set the PI-MAX MCP On/Off switch to OFF.
2. Imaging application: Have the lens stopped down to its smallest aperture (typicallyf/16). For all experiments, it may be advisable to initially have the intensifier covered
with a black cloth and/or a lens cap over the lens, as well.
3. Spectroscopy application: Set the spectrograph entrance slit width to minimum(10 µm if possible).

Chapter 4First Light

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Turning on the System and Setting Up the Software
1. Turn on the ST-133.
Note: The PI-MAX overload alarm may sound briefly and then stop. This is normal
and is not a cause for concern. However, if the alarm sounds continuously, even withno light entering the spectrograph, something is wrong. Turn off the power andcontact the factory for guidance.
2. Turn on the computer power.
3. Start the WinX application software (WinView/32 or WinSpec/32 as appropriate).

Configuring the Software for Shutter Mode Operation
Setup menu
1. Select Hardware.
2. On the Controller/Camera tab, make the following settings.*
Use PVCAM: (WinX Versions 2.5.19.0 and earlier) If you are using theUSB 2.0 interface, verify that the box is checked.
Controller Type: ST133 for standard PI-MAX or ST-133-5 MHz for PI-MAX2
Version: 3 or higher
Camera Type: TH 512 × 512 7895, Marconi (EEV) 256 × 1024 (6 ph) CCD 30-11,
Kodak 1024 x 1024, Marconi 1024 x 1024 CCD 47-10, or RS 1340 × 1300 CCD
36-40 whichever array is installed in the camera.
Shutter Type: Electronic
Readout Mode: Full Frame (or Interline for Kodak 1024 x 1024)
LOGIC OUT Output: Shutter
User Defined Chip: not checked
User Defined Timing: not checked
RS170 Type: NTSC or PAL, according to your video monitor type.
Note: RS170 is not currently supported under USB 2.0 or by PI-MAX2 cameras.
3. On the Cleans/Skips tab, make the following settings.
Number of Cleans: 1
Number of Strips per Clean: 4
Minimum Block Size: 16
Number of Blocks: 32
Note: Incorporating Cleans minimizes the dark current. However, if an External
Sync occurs while a Clean is in progress, the Clean will go to completion before theexperiment begins, introducing jitter that can be as large as one complete Clean
cycle. If the experiment can tolerate this level of jitter, then operation with Cleans = 1
is recommended. On the other hand, if the experiment requires that jitter be reduced
to an absolute minimum, then Cleans should be set to “0.” Note that the effect ofchanging the Cleans setting will only be visible if operating in the Fast mode as
selected on the Experiment Setup Timing tab.
* Instead of selecting parameters individually, another option is to open the Setup menu, selectLoad Factory Defaults and then From Controller to load the values stored in theController.

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4. Select Detector Temperature from the Setup menu. Set the temperature to-10°C. Temperature lock should occur within ten minutes. Perhaps another twenty
minutes will be required for maximum temperature stability to be achieved. To see
when the array temperature reaches and stabilizes at the target temperature, leave theDetector Temperature dialog open. When the target temperature is reached, thedialog will report that the Current Temperature has Locked.
Note: If you are using the USB 2.0 interface, the Detector Temperature dialog will
not display temperature information while you are acquiring data.

Acquisition menu
1. Select Experiment Setup
2. On the Main tab, make the following settings.
Exposure Time: 10 ms
CCD Readout: Use Full Chip
Intensifier
Gain: 8
Shutter Mode: selected
3. On the ADC tab, select the SLOW ADC Type if this selection is available.
4. On the Timing tab, make the following settings:
Timing Mode: Free Run.
Continuous Cleans: Checked.
Shutter Control: Normal checked.
Mode: Safe Mode
5. Click on OK to execute the selections and close the dialog.

Pulser
Because this procedure is being set up for Shutter Mode operation, no Pulser parametersneed to be entered. The ST-133 will gate the intensifier on and off based on the Exposure
time.

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Pre-Acquisition Check
Room Illumination
Shutter Mode operation has been selected for this First Light procedure to reduce thesetup complexity. However, there is a risk of overloading the camera. For operation in
the Shutter Mode, the room lighting should be subdued to where it is hard to see withthe eye. The camera is about 100 times more sensitive than the eye.

If Imaging with a Lens
1. Begin with an aperture of nominally f/16 (lens stopped down as far as possible).
2. Provide a suitable target at the focal distance.
3. Cover the lens.

If Taking Spectra
1. If using a spectrograph, set up to either take an image, or to bin on chip and use aregion of interest, reading out the data as a spectrum. This will require selecting Use
Region of Interest (ROI) on the Experiment Setup Main page followed by
specifying the ROI via the Experiment Setup ROI Setup page.
2. Block light from entering the spectrograph.
3. Mount a suitable light source, such as a mercury pen-ray lamp, in front of theentrance slit of the spectrograph. Any light source with line output can be used.
Standard fluorescent overhead lamps have good calibration lines as well, as do theneon bulbs commonly used as power-on indicators on power strips. If there are no“line” sources available, it is possible to use a broadband source such as tungsten for
the alignment. If this is the case, use a wavelength setting of 0.0nm for alignment
purposes.
Note: If you purchased an optical-fiber adapter and cable, install them only after the
regular alignment procedure has been successfully completed. Consult the Optical Fiber
Adapter manual for specific instructions.

Initial Data Acquisition
1. Verify that room or ambient lighting is subdued.
2. Set the PI-MAX MCP On/Off switch to ON.
Note: The PI-MAX overload alarm may sound briefly and then stop. This is normal
and is not a cause for concern. However, if the alarm sounds continuously, even withno light entering the lens or spectrograph, something is wrong. Turn off the powerand contact the factory for guidance.
3. If you are using a spectrograph, set the software to display a spectrum. With
WinSpec/32, this is done by selecting Layout on the Display menu and thenselecting Graph on the General tab. When viewing the spectrum, select a strip at
about mid-range on the CCD by setting the ROI in software.
4. At the computer, select Focus mode (WinX Acquisition menu). Data acquisition
will begin and each frame acquired will be displayed on the computer monitor. Since
the intensifier is covered, the PI-MAX lens is capped, or the entrance to thespectrograph is covered, only noise will be displayed.

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4. Carefully uncover the intensifier, unblock the spectrograph entrance slit, and/or
remove the lens cap. The displayed images should now contain real data over a noisebackground. If the target is illuminated by overhead fluorescence, some images will
be bright and some dark. This occurs because the fluorescent lights flash at 120 Hz(2× 60 Hz line frequency). Because the data acquisition is not synchronized with theline, some images will be acquired at the instant when the lights are on, and others
will be acquired at the instant when they are off.
Note: If the overload warning sounds continuously, immediately cover theintensifier with a black opaque cloth, cap the lens, or reduce the room illumination
further.
5. Make adjustments for a good image or spectrum.


If the image or spectrum is washed out because the CCD is saturated, reduce theexposure time or the light falling on the intensifier. If it is too dark, increase theexposure time.



If using a lens, adjust the lens aperture to maximum (smallest f/ number) possible
without the alarm sounding. If necessary, decrease the set Exposure Time toobtain the best viewable (but not yet focused) image as the aperture opens.

6. To stop Focus operation without storing the current frame, click on the Stop icon (orselect Stop Acquisition on the Acquisition menu). To store the current frame andstop focus operation, click on the Start Storage icon (or select Start Storage on the
Acquisition menu).

Focusing
Instructions for focusing C-mount and F-mount lenses are provided in Appendix D.
Instructions for focusing the detector on a spectrograph are provided in Appendix E.

Final Comments
This completes the First Light directions. If you have followed the instructions, you
should have verified the basic operation of your system and performed initial focusing.
Subsequent chapters provide more information about operating a PI-MAX system,
including a chapter about operating factors that should be considered for both Shutter andGate modes of operation and separate chapters to discuss specific setup and operating
considerations for these modes.

Chapter 5General Operation Factors
Introduction
The purpose of the First Light chapter was to help you get your system up and running so
you could verify that it worked. The step-by-step procedures provided the appropriate
settings but did not explain why those settings were selected. The information in thischapter covers general operation factors that apply to both Shutter Mode and Gate
Mode operation of the PI-MAX system. These factors play a part before, during, andafter the exposure and readout of the CCD array: dark charge, clean cycles, continuous
cleans, exposure modes, readout, digitization, software binning, and backgroundsubtraction. Factors that are specific to a particular intensifier mode and pulser are
included in the appropriate chapter.

Data Acquisition Sequence
When data is acquired, the CCD array is exposed to an incoming signal, which integrates on
the array. At the end of the exposure time, the charge from the array pixels must be read out,
digitized, and transferred to the computer before the image from the array appears on thecomputer screen. This sequence is shown in the block diagram below (Figure 14).

Figure 14. Block Diagram of Signal Path in Standard PI-MAX System

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USB 2.0 and System On/Off Sequences
The following on/off sequences are specific to the USB 2.0 interface:
1. The ST-133 must be turned on before the WinX application software (WinView/32
or WinSpec/32) is opened to ensure communication between the controller and thecomputer. If the WinX application is opened and the ST-133 is off, many of thefunctions will be disabled and you will only be able to retrieve and examine
previously acquired and stored data. You must close the WinX application software,
turn on the ST-133, and reopen the WinX application software before you can set
up experiments and acquire new data.
2. The WinX application software must be closed before turning off the ST-133. If
you turn off the ST-133 before closing the WinX application software, thecommunication link with the controller will be broken. You can operate theprogram in a playback mode (i.e., examine previously acquired data) but will be
unable to acquire new data until you have closed the WinX application software,
turned on the ST-133, and then re-opened the WinX application software.

Pre-Exposure Removal of Accumulated Charge
Introduction
The purpose of the CCD array is to acquire a signal of interest that can then be digitizedand transmitted to the host computer for storage, display, and post-processing. It will
acquire signal whenever the camera is connected to an ST-133 that is turned on, whether
or not the intensifier is being gated to take an exposure. If the intensifier is off, darkcharge will be the main source of signal accumulation on the array. To counteract this,clean cycles, and continuous clean cycles are used to remove the dark charge while thecamera is waiting to acquire the signal of interest. Dark charge, clean cycles, andcontinuous clean cycles are described in the paragraphs that follow.

Dark Charge
As soon as the ST-133 is powered on with a connected PI-MAX camera, thermallyinduced charge will begin integrating on the CCD array even if the photocathode isbiased off. Because dark charge is thermally-induced, reducing the array temperaturesignificantly reduces the rate at which this charge accumulates in the pixel wells. Evenso, enough dark charge could accumulate in the pixels between data acquisitions to affectdynamic range at the beginning of an exposure. To prevent this from happening, clean
cycles repeatedly shift and discard any signal that has integrated on the array while theST-133 is waiting for a Start Acquisition command from the host computer.
After the Start Acquisition command is received, a final clean cycle occurs and exposure
begins. During the exposure time, both the signal of interest and dark charge integrate on thearray. The longer the exposure time and the warmer the camera, the larger and less uniformthe dark charge will appear. To minimize the dark charge contribution to the acquired signal,
you should operate with the lowest temperature possible for your camera. Reducing theexposure time may also be helpful.
To further reduce the dark charge contribution to an acquired signal, you may be able toperform background subtraction, which subtracts a dark charge background from raw dataacquired using the same experiment conditions (see "Background Subtraction", page 59).

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Notes:
1. Do not be concerned about either the DC level of this background noise or its shapeunless it is very high, i.e., > 1000 counts with 16-bit A/D. What you see is not noise.
It is a fully subtractable readout pattern. Refer to "Background Subtraction",
page 59, for more information.
2. Offset and excess noise problems are more likely to occur if the controller andcamera weren't calibrated and tested as a system at the factory.

CautionIf you observe a sudden change in the baseline signal you may have excessive humidity
in the camera's vacuum enclosure. Immediately turn off the controller. Then, contact
Princeton Instruments Customer Support for further instructions. See page 232 forcontact information.

Clean Cycles
As stated before, dark charge integrates on the array whenever the camera is on, whether or
not data acquisition is occurring. To minimize the dark charge and other noise in the pixel
wells when data acquisition is idle, the Clean Cycles function shifts accumulated charge in apredefined number of rows to the shift register and then discards it.
Clean cycles start when you turn the controller on and a clean pattern is programmed into theST-133. At the end of a cycle, the ST-133 checks to see if a Start Acquisition command has
been received. If it has been received, the user-defined number of cleans (typically 0) willbe then performed before the exposure time starts. If a Start Acquisition has not been
received, the next clean cycle begins.
The number of rows that are shifted and discarded during a clean cycle are defined in theapplication software (for example, on the WinView/WinSpec Hardware Setup|Cleans/
Skips tab). The most effective cleaning occurs when the number of rows equals the numberof rows on the CCD. However, you need to keep in mind that a clean cycle must becompleted before a Start Acquisition command will be implemented. The more rows in acycle, the greater the delay between the command receipt and the beginning of an exposure.
Because of this timing issue, the number of rows per clean cycle is usually much smaller than
the number of rows on the array.
The timing diagram below is for an experiment set up to acquire three (3) images in FreeRun timing mode with normal shutter operation selected. In this diagram, clean cycles
occur before the first exposure and after the last readout period. They do not need to occur
between exposures since each readout cleans the array before the next exposure starts.

Figure 15. Clean Cycles in Free Run Operation

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Note: The start of the exposure is signaled by the NOT SCAN output of theconnector going high but will not occur until the current clean cycle and the additionaluser-defined number of cleans (typically 0) have finished. "Number of Cleans" is definedon the Setup|Hardware Setup|Cleans/Skips tab. If you enter a value other than "0",you will further delay the start of the exposure by that number of clean cycles.

Continuous Cleans Cycles
The Continuous Cleans function is provided when the start of an exposure is tied to an
external trigger (i.e., the experiment is being run in External Sync timing mode) to ensurethat the array will continue to be cleaned until the External Sync pulse is received. The
continuous clean cycles are defined by the same parameter values as the standard clean
cycles. The difference is that continuous clean cycles occur between NOT SCAN goinghigh and External Sync pulse arrival. Continuous cleans cycles ensure that ambient lightand dark current signal integrating on the array is continuously removed while the ST-133
is waiting for an External Sync pulse after the receipt of the Start Acquisition signal.
Note: When the External Sync arrives during a continuous clean cycle, that cycle must
be completed before the exposure will begin. In time critical experiments, the number ofrows per clean (set on the Hardware Setup| Cleans/Skips tab) should be 1 or 2 tominimize the delay.
Figure 16 shows the timing diagram for an experiment with External Sync trigger activeon the negative edge. Note that the timing diagram shows two possible setups for thephotocathode. In the first setup (Normal), the photocathode is biased on when External
Sync goes low. Because it takes time to bias the photocathode on, part of the incoming
signal may be missed while the photocathode is turning on. In the second setup(PreOpen), the photocathode is biased on when the following conditions are met: thecommand is received, clean cycles finish, and the NOT SCAN signal goes high. The
advantage is that the photocathode is fully on when the exposure (triggered by ExternalSync) begins. The disadvantage is that ambient light is no longer being blocked from thearray. Continuous cleans provide a way to get rid of the signal that accumulates on thearray during that period.

Figure 16. Timing Diagram: External Sync without Continuous CleansChapter 5General Operation Factors

57

Figure 17 shows a timing diagram that is basically the same as the one shown in Figure 16.
The difference is the continuous cleans (indicated by the shaded areas labeled CC) that now
occur during tw (the waiting period during which External Sync will be accepted).

Figure 17. Timing Diagram: External Sync with Continuous Cleans

Shutter Compensation Time
Shutter Compensation Time is the amount time inserted between the end of the exposure
time and the beginning of the array readout. This amount of time is determined by the
Shutter Type choice on the Hardware Setup|Controller/Camera tab card). For a
PI-MAX, the appropriate choices are "Electronic" and "None". When "Electronic" isselected, 6 ms is inserted to allow time for the phosphor to decay: this choice isappropriate for a P43 phosphor. No time is inserted when "None" is selected: this choice
is appropriate for a P46 phosphor.

Temperature Control
WARNING

Under normal conditions, the front end of the camera is sealed and backfilled so there
is no danger of damage due to condensation.

Cooling Method
Cooling the CCD array reduces the amount of dark charge, thereby acting to improve thesignal-to-noise ratio. An internal Peltier device directly cools the cold finger on which the
CCD is mounted. The heat produced by the Peltier device is then removed by the air drawn
into the camera by the internal fan and exhausted through the back-panel grill. The fan isalways running and cooling the CCD and the internal electronics. Additional heat removal
can be performed by circulating water through an internal heatblock.
Air-cooling: With air-cooling alone, at an ambient temperature of 25C, temperaturelock at -20 should typically take ten to twenty minutes. Cooling performance isaffected by the CCD array being used (i.e., larger arrays may take longer to cool than

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smaller arrays). Also, if the lab is particularly warm, achieving temperature lockmight take longer or not be obtainable at all.
Supplemental Water-cooling: Allows temperature lock to be achieved more rapidly
than would be required to lock at the same temperature with air-cooling alone. In
addition, it will be possible to achieve temperature lock at lower temperatures,
typically three or four degrees lower than would be possible with air-cooling alone.

WARNING

Cooling performance can be enhanced by circulating water with a temperature below
laboratory ambient but this approach will increase the risk of condensation inside the
PI-MAX. This condensation can cause catastrophic failure of the detector electronics. Any
resulting damage would be considered to have resulted from improper operation and will not
be covered by the Warranty. Even ordinary tap water is too cold to be used without risk! For
safety, the water should be no colder than the laboratory ambient temperature. Closed
circulation systems that depend on ambient air-cooling of the circulating water will generally
give good results. If you feel that you must use water colder than the laboratory ambient
temperature, it is absolutely essential that the PI-MAX be operated where the humidity is low
enough to prevent internal condensation. If the coolant is below the freezing temperature ofwater, we advise using a mixture of 50% water and 50% ethylene glycol as the coolant.
The easiest and most practical way to achieve the required low humidity is to put the
PI-MAX inside a plastic bag and to then purge the bag with a continuous flow of dry
nitrogen. On completion of the experiment, be sure to continue the purge until the
PI-MAX’s internal cold surfaces have had time to warm to the ambient laboratory
temperature. Contact the factory if you require additional information.

See "Making the Coolant Circulator-Camera Connections", page 44 for additional
information regarding the use of water with a temperature below laboratory ambient.

Setting the Temperature
Regardless of the type of cooling, the CCD array temperature is set via the software
Detector Temperature dialog, accessed by selecting Detector Temperature on the
Setup menu (WinView/32 or WinSpec/32). Temperature lock to a set temperature in theoperating range will typically occur within ten minutes. Perhaps another twenty minutes
will be required for maximum temperature stability to be achieved. To see when the arraytemperature reaches and stabilizes at the target temperature, leave the Detector
Temperature dialog open. When the target temperature is reached, the dialog willreport that the Current Temperature has Locked.
Note: If you are using the USB 2.0 interface, the Detector Temperature dialog will
not display temperature information while you are acquiring data.

Exposure
Data acquisition has two parts: exposure and readout. Exposure refers to the integrationof a signal of interest on the CCD array and readout is the transfer of the integrated signal
from the array pixels to a shift register and from there to a preamplifier. During exposure,each pixel in the two-dimensional grid of individual pixels senses the intensity of lightfalling on its collection area and stores a proportional amount of charge in its associatedChapter 5General Operation Factors

59well. Once charge accumulates for the exposure time (set in the application software), thepixels are read out serially.
Because CCD arrays are always sensitive to light, light must not be allowed to fall on thearray during readout (with a few exceptions). Intensified cameras such as the PI-MAX
rely on gating the intensifier off, to prevent light from reaching the array. During eachdata acquisition, the intensifier is gated on for the duration of the exposure time, allowing
the pixels to register light, and is then gated off for the readout period.

Exposure with an Image Intensifier
PI-MAX cameras use an image intensifier both to gate light on and off and to greatly
increase the brightness of the image. In these cameras the image intensifier detects andamplifies the light, and the CCD is used for readout.
The exposure programmed by software in this case refers to duration of gating of theintensifier. For shorter exposures, a PTG or a DG535 timing generator is required.
The MCP (microchannel plate) of the intensifier is composed of more than 106 individual
miniature electron multipliers with an excellent input to output spatial geometricaccuracy. Intensifier gain is varied by adjusting the voltage across the MCP or the voltage
across the MCP output and the phosphor. This second parameter is a factory adjustment,
as it affects both the gain and the resolution of the intensifier.
Detection of extremely weak Continuous Wave (CW) signals, e.g., luminescence and Raman
scattering from solid state samples, is typically limited by the dark current of the intensifier's
photocathode, usually referred to as the equivalent brightness intensity (EBI). All standard
intensified cameras made by Princeton Instruments have the lowest EBI values possible.

Saturation
When signal levels in some part of the image are very high, charge generated in one pixel
may exceed the "well capacity" of the pixel, spilling over into adjacent pixels in a process
called "blooming." In this case a more frequent readout is advisable, with signal
averaging to enhance S/N (Signal-to-Noise ratio) accomplished through the software.
For signal levels low enough to be readout-noise limited, longer exposure times, andtherefore longer signal accumulation in the CCD, will improve the S/N ratio
approximately linearly with the length of exposure time. There is, however, a maximum
time limit for on-chip averaging, determined by either the saturation of the CCD pixels
by the signal or the loss of dynamic range due to the buildup of dark charge in the pixels.

Background Subtraction
Each CCD has its own dark charge pattern or background that can be subtracted from thetotal acquired signal. By subtracting this background, you can eliminate the dark charge,
which might otherwise hide low-intensity signal.
When setting up for background subtraction, set up the experiment conditions foracquiring the actual image (camera temperature, exposure time, region of interest, timing
mode, etc.) and then, while blocking the incoming signal from the array, acquire a darkcharge "background image" under those conditions. Once the background image isacquired, save it to disk.
After storing the background data to disk, you have two choices for backgroundsubtraction: automatic or post-processing.

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Automatic: This approach requires that you activate "Background" and specify the
background filename on the Acquisition|Experiment Setup…|Data Corrections
tab before acquiring an image. When you acquire an image, the specified backgroundfile data will automatically be subtracted from the raw image data before thecorrected data is displayed and is available for storage to disk.

Post-Processing: If you prefer to acquire and preserve the raw image data, make surethat "Background" is not active on the Acquisition|Experiment Setup…|Data
Corrections tab. Then, acquire the image, save the raw image data to disk, and, via
the Image (or Spectra) Math function (accessed from the Process menu), subtract
the background file data from the raw image data. The subsequent data can then be
saved to a separate file.

Readout of the ArrayAt the end of the exposure time, the charge from the pixels is shifted to the shift register,
amplified, and digitized. In this section, a simple 6  4 pixel CCD is used to demonstrate how
charge is shifted and digitized. As described below, three different types of readout areavailable: full frame, interline, and binned. Full frame readout, for full frame CCDs, reads out
the entire CCD surface at the same time. Interline readout, for interline CCDs, can readout thearray using either overlapped or non-overlapped mode. Binned readout (also known as
Hardware Binning) adds the charge from adjacent pixels together to form a single pixel(sometimes called a super-pixel) before the preamplifier reads out the signal.

Full Frame Readout
The upper left drawing in Figure 18 represents a CCD after exposure but before thebeginning of readout. The capital letters represent different amounts of charge, including
both signal and dark charge. This section explains readout at full resolution, where every
pixel is digitized separately.
Readout of the CCD begins with the simultaneous shifting of all pixels one row toward
the "shift register," in this case the row at the top. The shift register is a single line of
pixels along one side of the CCD, not sensitive to light and used for readout only.
Typically the shift register pixels hold twice as much charge as the pixels in the imaging
area of the CCD.

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After the first row is moved into the shift
register, the charge now in the shift
register is shifted toward the output node,located at one end of the shift register. As
each value is "emptied" into this node it isdigitized. Only after all pixels in the firstrow are digitized is the second row moved
into the shift register. The order of shiftingin our example is therefore A1, B1, C1,
D1, A2, B2, C2, D2 ....
After charge is shifted out of each pixel theremaining charge is zero, meaning that thearray is immediately ready for the next
exposure.
A subsection of the CCD can be read out atfull resolution, sometimes dramaticallyincreasing the readout rate while retaining
the highest resolution in the region ofinterest (ROI). Note that some overhead
time is required to shift out and discard theunwanted pixels.

Figure 18. Full Frame at Full Resolution

Interline Readout

In this section, a simple 6  3 pixel interline CCD is used to demonstrate how charge isshifted and digitized. As described below, two different types of readout, overlapped andnon-overlapped can occur. In overlapped operation, each exposure begins while thereadout of the previous one is still in progress. In non-overlapped operation (selected
automatically if the exposure time is shorter than the readout time) each readout goes tocompletion before the next exposure begins.

Overlapped Operation Exposure and Readout
Figure 19 illustrates exposure and readout when operating in the overlapped mode.
Figure 19 contains four parts, each depicting a later stage in the exposure-readout cycle.
Eight columns of cells are shown. Columns 1, 3, and 5 contain imaging cells while
columns 2, 4, and 6 contain storage cells. The readout register is shown above the array.
Part 1 of the figure shows the array early in the exposure. The imaging cells contain charge
proportional to the amount of light integrated on each of them. The storage cells are empty
because no charge has been transferred to them. The arrows between adjacent imaging andstorage cells indicate the direction the charge will be shifted when the transfer occurs.
Part 2 of Figure 19 shows the situation early in the readout. The charge in the imaging
cells has been transferred to the adjacent storage cells and up-shifting to the readout
register has started. Note that a new exposure begins immediately.
Part 3 of Figure 19 shows the transfer to the output node. The lowermost cell in eachcolumn is shown empty. Each row of charges is moved in turn into the readout register,and from there to the output node and off of the array for further processing. The processcontinues until all charges have been completely transferred out of the array. The imaging
cells continue accumulating charge throughout the readout process. Integrating in thisway while the readout takes place achieves the maximum possible time efficiency.

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Version 5.GPart 4 of Figure 19 illustrates the situation at the end of the readout. The storage cells andreadout register are empty, but the ongoing accumulation of charge in the imaging cells
continues until the end of the programmed exposure.

Figure 19. Overlapped Mode Exposure and Readout

Non-Overlapped Operation Exposure and Readout
Figure 20 illustrates exposure and readout when operating in the non-overlapped mode.
Non-overlapped operation occurs automatically any time the exposure time is shorter
than the readout time. Figure 20 contains four parts, each depicting a later stage in the
exposure-readout cycle.
Part 1 of the figure shows the array early in the exposure. The imaging cells contain charge
proportional to the amount of light integrated on each of them. The storage cells are empty
because no charge has been transferred to them. The arrows between adjacent imaging andstorage cells indicate the direction the charge will be shifted when the transfer occurs.
Part 2 of Figure 20 shows the situation early in the readout cycle. The charge in the imaging
cells has been transferred to the adjacent storage cells and up-shifting to the readout registerhas started. Note that a second exposure doesn’t begin while the readout is in progress.
Part 3 of Figure 20 shows the transfer to the output node. The lowermost cell in eachcolumn is shown empty. Each row of charges is moved in turn into the readout register,and from there to the output node and off of the array for further processing. The processcontinues until all charges have been completely transferred out of the array. The imaging
cells are electronically switched off and do not accumulate any charge as the readout

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takes place. Because this scheme is less time efficient than that used in the overlappedmode, the frame rate may be lower in non-overlapped operation than it is in overlapped
operation with the some exposure time settings.
Part 4 of Figure 20 illustrates the situation at the end of the readout. Both the imaging andstorage cells are empty. In Free Run operation, the imaging cells will be switched back on
immediately, allowing charge accumulation to begin. In Ext Sync operation with no
PreOpen, they are not switched back on until after the External Sync pulse is detected.

Figure 20. Non-Overlapped Mode Exposure and Readout

A subsection of the CCD can be read out at full resolution, sometimes increasing thereadout rate while retaining the highest resolution in the region of interest (ROI).

Readout Rate for Interline
Below are the equations that determine the rate at which the CCD is read out. Tables ofvalues for CCDs supported at the time of the printing of this manual also appear below.
Assuming the shutter selection is None, the time needed to take a full frame at full
resolution in non-overlapped timing mode is:tR + texp
where
tR is the CCD readout time,
texp is the exposure time.

(1)

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The readout time is approximately given by:
tR = [Nx · Ny · (tsr + tv)] + (Nx · ti)

(2)

where
Nx is the smaller dimension of the CCD
Ny is the larger dimension of the CCD.
tsr is the time needed to shift one pixel out of the shift register
tv is the time needed to digitize a pixel
ti is the time needed to shift one line into the shift register
The readout rate in frames per second for the PI-MAX2:1003 Kodak 1024 × 1024
interline array running at 5 MHz is shown in Table 3.
Region of Interest Size
Binning1024 × 1024

400 × 400

200 × 200

1×1

4

10

17

2x2

8

17

27

4×4

15

27

37

Table 3. Readout Rates for Kodak 1024 × 1024 Array at 5 MHz

A subsection of the CCD can be read out at full resolution, sometimes increasing thereadout rate while retaining the highest resolution in the region of interest (ROI).

Binned Readout (Hardware Binning)
Introduction
Binning is the process of adding the charge from adjacent pixels together to form a single
pixel (sometimes called a super-pixel), and it can be accomplished in either hardware orsoftware. Rectangular groups of pixels of any size may be binned together, subject tosome hardware and software limitations.
Hardware binning reduces readout time and the burden on computer memory bysumming charge before the preamplifier reads out the signal. For signal levels that arereadout noise limited this method improves S/N ratio linearly with the number of pixels
grouped together. For signals large enough to render the camera photon shot noise
limited, the S/N ratio improvement is roughly proportional to the square-root of thenumber of pixels binned. In the WinX application, hardware binning is set up on the
Acquisition|Experiment Setup…|ROI Setup tab card by entering a value in theGroup fields: for example, a "2" in each of the Group fields will set up 2 x 2 hardware
binning.
Limitations of hardware binning include:

Lowered resolution because charge from adjacent pixels is summed into a super
pixel.



Increased possibility to blooming. Because shift register pixels typically hold only
twice as much charge as image pixels, the binning of large sections may result insaturation and spilling of charge back into the image area.

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65

Possible data loss if the total charge binned together exceeds the capacity of theshift register or output node.

The possibility of blooming or data loss strongly limits the number of pixels that may bebinned in cases where there is a small signal superimposed on a large background, such as
signals with a large fluorescence. Ideally, one would like to bin many pixels to increase theS/N ratio of the weak peaks but this cannot be done because the fluorescence would quickly
saturate the CCD. The solution is to perform the binning in software. Limited hardware
binning may be used when reading out the CCD. Additional post-processing binning isaccomplished in software, producing a result that represents many more photons than was
possible using hardware binning.

Full Frame CCD
Figure 21 shows an example of 2 
2 binning for a full frame CCD.
Each pixel of the image displayedby the software represents 4 pixelsof the CCD array. Note that in
WinSpec, Y-axis (slit) binningoccurs automatically: the Image
option must be installed andselected for any other binningformat to be available.

Figure 21. 2 × 2 Binning for Full Frame CCD

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Figure 22 shows an example of 2  2 binning. Each pixel of the image displayed by thesoftware represents 4 pixels of the CCD array. Rectangular bins of any size are possible.

Figure 22. 2 × 2 Binning for Interline CCD

Software Binning
Software binning is a software-averaging post-acquisition process that can be performed oneither unbinned or hardware-binned data. This type of binning can improve the S/N ratioby as much as the square root of the number of scans. Unfortunately, with a high numberof scans (i.e., above 100), camera 1/f noise may reduce the actual S/N ratio to slightly
below this theoretical value. Also, if the light source used is photon flicker (1/f noise)
limited rather than photon shot-noise limited, this theoretical signal improvement cannot
be fully realized. Again, background subtraction from the raw data is necessary.
Software binning is also useful in high light level experiments, where the camera is again
photon shot-noise limited. Summing multiple pixels in software corresponds to collecting
more photons, and results in a better S/N ratio in the measurement.
In the WinX application software, software binning can either be set up to occur
automatically or as a manual post-processing operation. Automatic software binning is
set up by entering Group parameters on the Acquisition|Experiment Setup…|ROI

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Setup tab card and then selecting the Use Software Binning checkbox. The drawback toautomatic binning is that the raw data is lost. Alternatively, you can acquire raw data andthen use the post-processing binning function (located on the Process|Binning andSkipping… dialog) to select the input data, enter the binning parameters, and save theresult to an appropriately named file.

Digitization
During readout, an analog signal representing the charge of each pixel (or binned groupof pixels) is digitized. The number of bits per pixel is based on both the hardware and thesettings programmed into the camera through the software.
For PI-MAX systems, the ST-133 has two complete analog channels including separate
A/D converters. Because the readout noise of CCD arrays increases with the readout rate,
it is sometimes necessary to trade off readout speed for high dynamic range. The two
analog converters, one optimized for high speed, the other for high precision, provide asolution to this problem. Switching between the channels is completely under software
control for total experiment automation.

Experiment Setup|Main
Typically, the first experiment setup
parameters are selected/entered on theExperiment Setup|Main tab. These
parameters determine such things as how longthe signal of interest will be allowed tointegrate on the CCD, the number of separate
frames (denoted as images or spectra) that will
be acquired, how much of the CCD will be
used to acquired data, the intensifier gain, andthe intensifier mode. The Main parameters aredescribed briefly below.

Exposure Time
Exposure time is the "time space" from whichcharge accumulating on the CCD will besummed into the reported data. When thesystem is being run in Shutter Mode and FreeRun or External Sync mode, the exposure timeis determined by the user-set value in theexperiment setup. When Shutter Mode andInternal Sync are active, the exposure time isset to zero (0). When Gate Mode is active, theintensifier controls what the CCD sees during
the exposure time.

Figure 23. Experiment Setup|Main tab

An exposure can be zero and still have valid data, provided the CCD is not clearing off
charge acquired before the integration time: this is the condition of External Sync withno cleans, and the integration time is 'unofficially' started at either the Start Acquisitioncommand or from the last readout. This is contrary to External Sync Continuous
Cleans in which accumulated charge is removed prior to the integration time.

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Number of Images/Spectra and Accumulations
This is the number of sequential frames the software will collect and store in a single file.
Each frame will be digitized and stored, but all of the frames will be in a single file. A frame
may contain data from more than one region of interest as defined via the ROI Setup tab.
If the Accumulations > 1, each stored frame will contain summed data sets from two
or more exposures. The number of separate frames stored will the same as it would be forAccumulations =1, but the total number of exposures required would be the product of
the Number of Images/Spectra parameter times the Accumulations value.

CCD Readout
This parameter selection determines whether the entire CCD array will be used to acquirea frame or if only a rectangular portion (or portions) of the array will be used. When Use
Region of Interest is selected, data will be collected from the region(s) defined on ROI
Setup tab. The full chip size or the sum of the active region(s) as defined on the ROI tab
is displayed.

AmplifierIf the CCD is a Thomson 512 × 512 CCD array, either the high-capacity (fast) or the lownoise array output node can be selected. The actual selection is made by selecting FAST
(high capacity) or SLOW (low noise) on the Experiment Setup|A/D tab. The parameter
indications High Capacity and Low Noise on the Experiment Setup|Main tab arereported values only. The default setting is read from non-volatile RAM (NVRAM) in the
PI-MAX. If the selection is changed, the new setting is written to the NVRAM andbecomes the new starting default.
High Capacity: Allows the camera to collect 16-bit images at a readout rate of
up to 1 million pixels per second.



Low Noise: When operating at a lower speed, the camera provides superior
noise performance.

Intensifier Gain
The Intensifier gain provides continuous adjustment over an arbitrary range of 0-to-255.
The default setting of 128 will give good results in many applications. Once the ST-133
is turned on, the gain can be adjusted any time during image acquisition. We suggest
beginning with a low setting and then increasing it until optimum results are obtained.
Note: The intensifier gain also affects the dark charge of the intensifier (EBI). One resultof this is that, to properly perform background subtraction, a new background must be
taken whenever the intensifier gain is changed.

Intensifier Mode
The Intensifier Mode selection determines whether the intensifier will act as a mechanicalshutter that is biased on or off based on the set exposure time (Shutter Mode), it will bebiased on or off by the defined pulser gate timing (Gate Mode), or it will be continuously
biased off until either Shutter mode or Gate mode is selected (Safe Mode).

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Experiment Setup|Timing
Experiment setup requires the selection of avariety of experiment timing parameters. The
parameters described in this section are thosethat appear on the Experiment Setup|Timing
tab (Figure 24). With the exception of Fast
Mode/Safe Mode, which is described in full,
the following paragraphs briefly describe thesetiming parameters. The settings appropriate to
the intensifier mode and selected pulser are
discussed in Chapter 6 "Shutter Mode
Operation", Chapter 7 "Gated Operation with aPTG", and Chapter 8 "Gated Operation with a
DG535".

Timing Mode
The timing mode parameter refers to theST-133's synchronization of data acquisition
with an external TTL signal applied to the Ext
Sync connector on the back of the ST-133 oran internal trigger generated by a PTG. The
modes available depend on the selected
intensifier mode (Shutter, or Gate) and theselected pulser (None, PTG, or DG535).
Figure 24. Experiment Setup|Timing
dialogShutter Control
Since the ST-133 is gating the photocathode on and off as if it were a mechanical shutter,
you may have the choice of Normal, Disabled Closed, or Disabled Open "shutter"settings. Normal is available for the Free Run and External Sync timing modes.
Disabled Closed simply means that the photocathode will not be gated during theexperiment and is useful for acquiring background frames. Disabled Open is required for
the PTG Internal Sync control. Additionally, the PreOpen checkbox is only available for
the External Sync modes and for Internal Sync for PTG: PreOpen biases thephotocathode on before data acquisition is started.

Fast Mode or Safe Mode
The Fast Mode or Safe Mode selection determines whether the ST-133 will run theexperiment according to the experiment timing, with no interruptions from the computer,or the computer will interrupt the acquisition flow to process each frame as it is received.
Figure 25 compares the two modes.
Fast Mode operation is primarily for collecting “real-time” sequences of experimental
data, where timing is critical and events cannot be missed. Once the ST-133 is sent theStart Acquisition command by the computer, all frames are collected without further
intervention from the computer. The advantage of this timing mode is that timing iscontrolled completely through hardware. A drawback to this mode is that the computer
will only display frames when it is not performing other tasks. Image display has a lower
priority, so the image on the screen may lag several images behind. A video monitor
connected to the VIDEO output will always display the current image. A second

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drawback is that a data overrun may occur if the number of images collected exceeds theamount of allocated RAM or if the computer cannot keep up with the data rate.
Safe Mode operation is primarily useful for experiment setup, including alignment andfocusing, when it is necessary to have the most current image displayed on the screen. It
is also useful when data collection must be coordinated with external devices such asexternal shutters and filter wheels. As seen in Figure 25, in Safe Mode operation, thecomputer controls when each frame is taken. After each frame is received, the detector
sends the Stop Acquisition command to the detector, instructing it to stop acquisition.
Once that frame is completely processed and displayed, another Start Acquisitioncommand is sent from the computer to the detector, allowing it to take the next frame.
Display is therefore, at most, only one frame behind the actual data collection.
One disadvantage of the Safe mode is that events may be missed during the experiment,
since the ST-133 is disabled for a short time after each frame.

Delay Time
Allows a delay to be inserted between successive frame acquisitions. This parameter is only
active in Safe Mode operation, in which each frame must be completely processed before thenext one can be taken. The Delay Time inserts an additional delay after the computer has
finished processing the previous frame before the next one can be acquired.

Wait for TTL and TTL Line
When checked, acquisition will not begin until a TTL high (Level 1) is detected on thespecified line of the ST-133's TTL In/Out connector. For example, suppose Wait for
TTL and TTL Line 2 were selected, and you then clicked on Focus or Acquire. Data
collection would not begin until additionally, a TTL high was detected on TTL Line 2 ofthe controller’s TTL In/Out connector. Note that data acquisition, once initiated, cannot
be halted by reversing the TTL state on the selected line.
With Wait for TTL selected in Ext. Sync. mode operation, after detecting a TTL 1 on
the specified line, the system still waits for the External Sync edge before data acquisition
is initiated.
Notes:
1. TTL In/Out control is not currently supported under USB 2.0.
2. TTL control is further described in Chapter 13, starting on page 149.

Edge Trigger
When running in Ext. Sync. mode, this parameter setting determines whether
synchronization will take place on the positive-going or negative-going edge of theExternal Sync signal.

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Figure 25. Safe Mode and Fast Mode Operation

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Chapter 6
Shutter Mode Operation
Introduction
Shutter Mode is the simplest PI-MAX intensifier operating mode and, as in Chapter 4, canbe used to verify initial operation and to focus the camera and/or spectrograph. In Shutter
Mode operation, intensifier gating is under the control of signals from the ST-133. Thesesignals are applied to the PI-MAX via the cable connected to the Power/Signal connector.
Their generation and timing are under software control and the ST-133 treats thephotocathode as if it were a mechanical shutter. With the exception of the Internal Sync
(PTG) timing mode, the photocathode is held biased ON during the selected exposure time,allowing the PI-MAX to see light continuously during that time, and is biased OFF for thereadout period.
Note: No timing generator is needed for Shutter Mode operation.

CablingWith the exception of the Internal Sync (PTG) timing mode, a timing generator is not
used in Shutter Mode operation.


If a PTG is installed in the ST-133, older systems require that cable to the PI-MAX's
Timing Gen. connector be disconnected; newer systems ignore the connector when
Shutter Mode is being used.



If a DG535 is cabled to the PI-MAX and the ST-133, the DG535 should be powered
down or the cables to the ST-133 Ext. Sync connector and to the PI-MAX's Timing
Gen. connector should be disconnected.

Shutter Control
Since the ST-133 is gating the photocathode on and off as if it were a mechanical shutter,
you have the choice of Normal and PreOpen "shutter" settings. Normal is available for
the Free Run and External Sync timing modes. PreOpen is only available for theExternal Sync modes and Internal Sync for PTG.


Normal: The photocathode is biased on and off in synchronism with system timing.
With External Sync and External Sync with Continuous Cleans modes, photocathodegating is controlled by the External Sync pulse. The ST-133 waits for the pulse andthen gates the photocathode on for the set exposure time. As soon as the exposure iscomplete, the photocathode is biased off, the shutter compensation time elapses, andthe array is read out.

PreOpen: Available in the External Sync and External Sync with Continuous Cleansmodes, photocathode gating is only partially synchronized to the experiment. The
photocathode is gated on as soon as the ST-133 is ready to receive an External Sync
pulse. When the External Sync pulse arrives at the Ext Sync input, the photocathoderemains on until the end of the set exposure time, the photocathode is biased off, the73

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shutter compensation time elapses, and the array is read out. If additional frames areto be acquired, the photocathode will be gated on again and the ST-133 will wait for
an External Sync pulse.
PreOpen would be selected for experiments in which the event occurs before thephotocathode would have time to gate on (i.e., the time between the External Sync
pulse and the event is shorter than the propagation delay between the External Sync
pulse and the time it takes to bias the photocathode on).
Note: The main drawback to this shutter setting is that the CCD is exposed to any
ambient light while the photocathode is gated on between frames. To counteract
signal integration during this period, you could choose Continuous Cleans.

Timing Modes
Timing Mode

"Shutter" Control Pulser Ext Trigger Input

Free Run

NormalNone

None

External Sync

NormalNone

Ext Sync BNC

External Sync

PreOpenNone

Ext Sync BNC

External Sync w/Continuous Cleans

NormalNone

Ext Sync BNC

External Sync w/Continuous Cleans

PreOpenNone

Ext Sync BNC

PreOpen, Disabled Open

PTG

Ext. Trig. In. BNC

Internal Sync

Table 4. Timing Mode, Shutter Control, Ext. Trigger Input for Shutter Mode

The timing mode selection determines when signal integration will begin and end on the
CCD array and when the acquired signal will be read out. The following three timing
modes are available in Shutter Mode:Free Run: One cycle follows another automatically at the fastest frame ratepossible. The intensifier is gated on for the set Exposure Time during each cycle,
gated off at the end of the exposure time, and then read out. Any External Sync
signals are ignored.

External Sync: A suitable signal from an external source must be applied to theST-133’s Ext. Sync input. When the External Sync pulse is detected, the intensifier
will be gated on and pass light to the CCD for the set Exposure Time, will be gated
off at the end of the exposure time, and CCD array readout will occur. The
Accumulations and Images parameters remain active; the proper number of pulses
need to be applied to finish the experiment. Note that when Continuous Cleans isselected, there will be a delay between the time that the intensifier is gated on and thestart of the desired signal integration on the CCD array.

Internal Sync: (PTG only) This timing mode is only available if there is a PTG
installed in the ST-133. If Internal Sync is selected, the PTG will control the timingof the camera as if the camera were in External Sync mode and the PTG was theexternal trigger source. The PTG also has its own External Trigger In BNC that
accepts a wide variety of inputs, as opposed to the External Sync of the ST-133,
which only accepts TTL levels.
In order for the ST-133 to see signals from the PTG when Internal Sync is selected,
the following parameters should be set as indicated:

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Continuous Cleans: Disabled
Shutter Type: Electronic Shutter
Trigger Polarity: Negative edge

Timing Modes and Cleans/Continuous Cleans
This section provides timing diagrams, grouped by timing mode, to further describe thepurpose and timing of clean cycles and continuous clean cycles. See Chapter 5, for general
information about Clean cycles and Continuous Cleans cycles.

Free Run
The timing diagram below is for an experiment set up to acquire three (3) images in FreeRun timing mode with normal shutter operation selected. In this diagram, clean cycles
occur before the first exposure and after the last readout period. They do not need to occur
between exposures since each readout cleans the array before the next exposure starts.

Figure 26. Clean Cycles in Free Run Operation

Note: The start of the exposure is signaled by the NOT SCAN output signal of theconnector going high but will not occur until the current clean cycle and the
additional user-defined number of cleans have finished. "Number of Cleans" is defined on
the Setup|Hardware Setup|Cleans/Skips tab. If you enter a value other than "0", youwill further delay the start of the exposure by that number of clean cycles.

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External Sync
Figure 27 is a flowchart thatshows the sequence of actions
depending on the type of
Shutter Control. Figure 28 is atiming diagram of the same
sequences with an External
Sync trigger active on thenegative edge. In the first setup(Normal), the photocathode isbiased on when External Sync
goes low. Because it takes sometime to bias the photocathodeon, part of the incoming signal
may be missed while this ishappening. In the second setup(PreOpen), the photocathode is
Figure 27. Flowchart of Two External Sync Timing Options inbiased on when the following
Shutter Modeconditions are met: the Start
Acquisition command is received, clean cycles finish, and the NOT SCAN signal goeshigh. The advantage is that the photocathode is already biased on when the exposure(triggered by External Sync) begins. The disadvantage is that ambient light is no longer
being blocked from the array. Continuous cleans provide a way to get rid of the signalthat accumulates on the array during that period.

Figure 28. Timing Diagram: External Sync

Figure 29 shows a timing diagram that is basically the same as the one shown in Figure 28.
The difference is the continuous cleans (indicated by the shaded areas labeled CC) that now
occur during tw (the waiting period during which External Sync will be accepted).

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Figure 29. Timing Diagram: External Sync with Continuous Cleans

Further information about the sequence of events for External Synchronization is detailed
below based on Shutter Control setting, Clean Cycles, and Continuous Cleans









Ext Sync & Shutter Control = Normal
Normal clean cycles occur while waiting for the Start Acquisition command.
When it is received, a final clean cycle occurs and then the controller waits for
the Ext Sync to appear at its Ext Sync BNC. When it occurs, the photocathode isbiased on and signal of interest integration begins on the array. Dark charge
accumulates on the array in the time between the end of the last clean cycle andthe arrival of the Ext Sync.
Ext Sync & Shutter Control = PreOpen
Normal clean cycles occur while waiting for the Start Acquisition command.
When it is received, a final clean cycle occurs and the photocathode is biased on.
The controller waits for the Ext Sync to appear at its Ext Sync BNC. When it
occurs, the signal of interest integration begins on the array. Dark charge
accumulates on the array in the time between the end of the last clean cycle andthe arrival of the Ext Sync.
Ext Sync w/ Continuous Cleans & Shutter Control = Normal
Normal clean cycles occur while waiting for the Start Acquisition command. When it
is received, clean cycles continue to occur while the controller waits for the Ext Sync
to appear at its Ext Sync BNC. When it occurs, the current clean cycle goes tocompletion, the photocathode is biased on, and signal of interest integration begins
on the array. Dark charge accumulation on the array is minimized during the time
between the receipt of the Start Acquisition command and the arrival of the Ext
Sync.
Ext Sync w/ Continuous Cleans & Shutter Control = PreOpen
Normal clean cycles occur while waiting for the Start Acquisition command.
When it is received, the photocathode is biased on and clean cycles continue tooccur while the controller waits for the Ext Sync to appear at its Ext Sync BNC.

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When it occurs, the current clean cycle goes to completion, signal of interest
integration begins on the array. Ambient light and dark charge accumulation on
the array is minimized during the time between the receipt of the Start
Acquisition command and the arrival of the Ext Sync.

Internal Sync (PTG)
Clean cycles function as previously described. However, the Continuous Cleans function isdisabled.

Figure 30. Timing Diagram: Internal Sync (PTG)

Figure 31. Timing Diagram: Internal Sync with an External Trigger

External Triggering
When an External Sync timing mode is selected, the ST-133 waits for the Start
Acquisition command from the computer and a TTL level change (negative- or positiveedge as set on the Experiment Setup|Timing tab) to occur at the Ext Sync BNC
before starting the exposure time. The camera will begin the data acquisition cycle asChapter 6

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soon as the current clean cycle ends. The data acquisition cycle includes the exposure
time, shutter compensation time (unless Shutter Type is None), and the readout time.
If a PTG is installed in the ST-133 and Internal Sync is selected, the PTG will act as if itwere an external trigger source. In turn, the PTG can be triggered to start by an external
trigger inserted at its Ext. Trig. In. BNC. If you want to use an external trigger to trigger
the PTG, you must go to the PTG|Triggers tab and enter the characteristics of an
external trigger that, when input at the Ext. Trig. In BNC, will trigger the PTG's internal
pulse.

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Chapter 7
Gated Operation with a PTG
Introduction
This chapter discusses gated operation with a PTG and aspects of operation of the
PI-MAX not covered in Chapter 4, First Light. We additionally suggest that you review
Chapter 11, Tips and Tricks, which contains information that should prove helpful ingetting good results in more complex measurements.
Gate Mode operation is more complex than Shutter Mode operation because of theadditional cabling and timing considerations that apply. However, it is in gated operationthat the PI-MAX achieves its maximum power and utility, able to recover extremely faintfast signals in the presence of large ambient light levels.

Gating provides electronic shutter action by controlling the photocathode bias, allowing
the detection of low light level signals in the presence of interfering light sources of muchgreater energy. For instance, in combustion research, a pulsed laser probe is used toinvestigate the chemistry within a flame. Since the flame itself emits broadband light
continuously, the integrated flame emission is much greater than the integrated signal
resulting shortly after the laser probe (such as laser-induced fluorescence or Raman).
Fortunately, since the laser pulse is very short and the time at which it occurs is known, it
is possible to gate for a few nanoseconds during the laser pulse, thus reducing the flame
emission interference by approximately the measurement duty factor ratio.
Exposure time is the 'time space' from which charge integrating on the CCD will get
summed into the reported data. Gate width is the time during which light will be detectedby the intensifier, intensified, and applied to the CCD. Basically, the intensifier controls
what the chip 'sees' during the exposure time.
For signal to be detected, it must both fall in a valid gate width and in a valid exposure
time. Many gate pulses can be placed into one exposure time at random intervals because
there is no temporal measure inside a given exposure (all incident signals get summed(integrated) into one value per pixel / superpixel inside a given exposure).
Using presently available image intensifiers and gate pulse generators, optical gate times
 2 ns FWHM (full width at half maximum) are possible. Since the control is electronic,
the gate width can be made virtually as long as desired, allowing a wide range ofexperiment requirements to be satisfied in one instrument setup. Further, in UV
measurements, where the On:Off ratio is only 104:1, the PI-MAX’s MCP bracketingfeature can be used to extend the On:Off ratio to 106:1.

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Precautionary Measures
WARNING

Intensified CCD detectors, such as the PI-MAX, when biased ON, can be irreparably
damaged if continuously exposed to light levels higher than twice the A/D saturationlevel. Thus it is critical that you not establish conditions that could result in damage tothe intensifier. Although intensified detectors are less prone to damage from backgroundlight when operated gated, they are at significant risk of damage from high-intensity lightsources such as lasers. High intensity sources can damage the intensifier before theprotection circuits have time to respond, or even cause spot damage without theprotection circuits acting at all. In Shutter Mode operation, it will be necessary to keep
the lab lighting be subdued when working with an intensified detector. If a sustained
alarm indication occurs when the controller is turned on, immediately switch the MCP
On/Off switch on the back of the PI-MAX to the OFF position. Cover the detector
window and only switch the MCP On/Off switch to ON after the illumination level has
been lowered to safe operating conditions.

Intensifier Modes and Safety
The Experiment Setup Main screen allows selection of three modes, Shutter Mode,
Gate Mode and Safe Mode. In Shutter Mode operation, the photocathode is biased
on continuously during the exposure time and the room illumination must be subdued toprevent an overload alarm from occurring. In Gate Mode, the photocathode is biased on
only during the time each gate pulse* is applied. As a result, the tolerance to room light ishigher in gated operation, but the risk of damaging overload from intense light sources
such as lasers remains. Intense light sources in gated experiments can cause spot damage
that would be undetected by the alarm circuit. In Safe Mode, the photocathode iscontinuously biased OFF and the intensifier is as safe as it can be.

Alarm
To reduce the risk of detector damage, the PI-MAX detector is equipped with an audible
alarm in the detector head, activated when the intensity of light falling on the image
intensifier exceeds a preset threshold. While the alarm is sounding, the photocathode isdisabled. Immediately toggle the MCP On/Off switch (on the back of the PI-MAX) to
the OFF position. Cover the detector window and only switch the MCP On/Off switch
to ON after the illumination level has been lowered. If the alarm sounds continuously
even when the illumination level is adequately low, shut the system down and contact thefactory for guidance.
Note: It is normal for the alarm to sound briefly when the system is turned on.

CautionDiscontinue operation and contact the factory at once if sporadic or continuous
unwarranted alarms occur. They may indicate intensifier damage or another situation that
requires immediate attention.

* The Gate pulse is produced inside the PI-MAX from the Start and Stop signals supplied by the

Timing Generator.

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Timing Mode
When you are in Gate Mode, the PTG will only operate using Internal Sync timing.
This timing mode initiates a readout cycle after each PTG pulse ensemble.* The
handshakes that prevent a readout from occurring while the PTG is busy and that prevent
the PTG from pulsing the photocathode ON while a readout cycle is in progress are
performed through the ST-133 backplane. For this mode, the following parameters areautomatically set by the application software and cannot be changed: Exposure Time isset to 0, Continuous Cleans is disabled, and Disabled Opened and PreOpen are
selected for Shutter Control.
Timing ModeControlled by PTG"Shutter" Control Ext Trigger Input
Controlled by PTG

Ext Trig In. BNC

Table 5. Timing Mode, Shutter Control, and Ext. Trigger Input
when a PTG is the Timing Generator

Note: The Accumulations and Images (or Spectra) parameters (WinView/32 or
WinSpec/32 Acquisition Setup Main tab) govern how the data will be processed.
Integrating multiple events on the CCD really brings the power of the PI-MAX to bear on
low-light gate-mode experiments. If the experiment allows, many pulses can be summed
on the CCD with no pulse artifacts in the readout. The signal increases nearly linearlywith the number of pulses (within limits imposed by the CCD).

Fast Gating
A particularly noteworthy feature of the PI-MAX is its ability to gate in as little as 2 ns orless when the PI-MAX has been configured with a fast gate intensifier. The camera’s
exceptional gating performance can be easily demonstrated with a straightforward
experimental setup.
The following fast-gated experiment was
performed using the PI-MAX camera with the
fast-gate option and operated in conjunction
with Princeton Instruments’ WinSpec/32
software, a Hamamatsu PL0-01 Picosecond
Light Source, and a PTG. Other equipment
included a computer and an ST-133 Controller.
To do the experiment, 60 ps pulses from theHamamatsu Light Source triggered from thetiming generator were applied to the PI-MAX
and a gated measurement was performed.

Sequential Gating Setup
Number of Spectra: 61
Start Gate Width: 2 ns
End Gate Width: 2 ns
Start Gate Delay: 102 ns
End Gate Delay: 105 ns
Increment Type: Fixed
Delay Increment: 0.05 ns* A PTG pulse ensemble consists of a Gate Start pulse, a Gate Stop pulse, and an Auxiliary pulse.

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Figure 32. PTG Fast Gating Experiment Block diagram

The WinSpec/32 software’s sequential gating function was used to increment the delay to
the PI-MAX gate in 50 ps steps. As a result, with respect to the applied light pulses, the
PI-MAX was gated 50 ps later with each repetition. The data from each pulse wascollected and displayed in a 3-D plot with time on the Z-axis. By sliding the coincidence
time of the gate and applied light pulses in this manner, a plot was produced that
accurately characterized the temporal profile of the PI-MAX fast gate function. The
measurement results are shown below. FWHM on the gate was 1.6 ns and the FW was
measured at 2 ns.

Figure 33. Fast Gating Measurement Results

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MCP Bracket Pulsing
Introduction
The principal utility of gating is that it allows temporal discrimination against backgroundlight. By allowing the photocathode to “see” only during the event of interest, very highbackground illumination levels can be tolerated without materially degrading experimentresults. The limit on this technique is set by the light leakage of the intensifier, which,although it is very good, is not without limit. In the visible, the on/off ratio of a typical Gen II
Intensifier with just the photocathode gated is excellent, typically between 106 and 107. In
most measurements, this ratio is sufficient to assure that the signal reaching the CCD during
the intensifier Off times will be too small to affect the data.
Below 350 nm, however, a second leakage mechanism occurs, optical leakage throughthe photocathode to the UV-sensitive MCP, which reduces the On:Off ratio to about 2 ×
104 at 200 nm. This is the dominant response of a Gen II image intensifier to UV photons
when the photocathode is electrically off. At an On:Off ratio of 20,000, the ability of acamera with conventional photocathode (only) gating to perform certain kinds ofmeasurements in the UV is adversely affected.
MCP bracket pulsing* keeps the MCP biased OFF except for an interval that brackets thetiming of the photocathode gate as shown in Figure 34. For emitted photoelectrons to beaccelerated in the MCP, the MCP must be biased ON. In conventional intensified
cameras, the MCP is biased ON continuously. In the PI-MAX, however, when bracket
pulsing is ON, the MCP is biased OFF until just before the photocathode is gated ON.
The MCP is then biased ON and remains biased ON until just after the photocathode isbiased OFF.

Figure 34. Timing: Bracket Pulsing

Traditionally, intensified detectors discriminated against background signal by gating thephotocathode. Although this technique yields very high peak Off/On ratios, on the orderof 5 × 106:1 in the visible, background signal can still prove troublesome in low-duty
factor measurements, particularly in the UV region where the rejection is only ~104 :1.
By bracket pulsing the MCP off (in addition to photocathode gating), the on/off ratio of
the PI-MAX in UV is improved by 2-3 orders of magnitude. The resulting UV ratio
exceeds even the high levels normally achieved in the visible. Applications that benefit
from this new approach include LIF and nanosecond pump-probe experiments.
Note: Bracket pulsing does not help in the visible region. Under extremely low dutyfactor conditions, the only remedy is to install an external shutter ahead of the camera.

*

Bracket pulsing is not available for cameras having a Gen III Intensifier. Gen III Intensifiers do
not respond in the UV.

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Bracket Pulsing in LIF Measurements
Most experiments using laser-induced fluorescence to probe combustion flows are
performed with UV probe/lasers. Atomic emission from flames also has significant UVcontent. If the flame is continuous, the UV background will also be continuous. Even
where a flame is transient (e.g. internal combustion engine), its lifetime can be many
milliseconds, compared to the nanosecond time scale of the laser used. This backgroundcan be a million times as long. If the background is bright, then a UV on/off ratio of
20,000:1 will be overwhelmed by the duty cycle and will not be adequate for extracting asignal of 10-5. In high dynamic range quantitative measurements, backgrounds must be
kept to an absolute minimum. MCP bracket pulse gating dramatically improves therejection of CW and even millisecond time-scale background.
An alternative to suppressing background for imaging has been the use of very narrowspectral bandpass filters. In the UV, these filters are expensive and they can have lowtransmission at their central wavelength. An additional filter is required for eachwavelength to be imaged. The use of electronic temporal rejection of CW or quasi-CW
background may make it unnecessary to use these filters, thus increasing the opticalthroughput, sensitivity, and quantitative precision of the measurement.

Bracket Pulsing in Nanosecond Pump Probe Experiments
Some nanosecond pump-probe experiments combine a nanosecond or faster pump with aflashlamp probe. The duration of the probe flash can be 10-50 µs and a gate is used to
select the specific nanosecond-scale time slice to be observed within the much longer
probe flash. In these absorbance experiments, accurate measurement of absorbancevalues depends critically on the lack of stray light contamination, particularly at moderate
to high optical density levels. Selecting a 5 ns time window out of a 10 µs pulse isalready one part in 2,000. If UV leakage gives an on/off ratio of only 20,000:1,
contamination could be 10% of higher. This would limit the optical density to 1.0, and it
could make linear quantitation difficult beyond 0.1 OD.
MCP bracket pulse gating can substantially improve the on/off ratio in such an
experiment. Even with a 1 µs MCP pulse, the rejection of flash-lamp leakage can add
more than an order of magnitude of range, to 2.0 OD.

Limitations of Bracket Pulse Gating
MCP bracket pulse gating is most useful in rejecting background that lasts microseconds
up to CW. Fast transient backgrounds can be in the form of stray laser light scattering(Raleigh, MIE, Raman) or unwanted fast fluorescence. Because these usually fall below
the MCP bracket pulsing 1 µs delay restriction, these measurements cannot be improved
by MCP bracket pulsing in the PI-MAX.
Electrically, gating the MCP will only reduce leakage at wavelengths where the MCP has
photoelectric response (primarily in the UV). Thus, for visible and NIR wavelengths
where leakage is primarily optical, the improvement will be minimal (although the on/off
ratio is already very good in these regions). Note that in some spectroscopic applications,visible leakage may appear to be reduced by MCP pulsing. This is because the second
order UV spectrum overlays the first order visible spectrum in a grating spectrograph.
MCP pulsing can eliminate unwanted sensitivity to CW or quasi-CW second order UV,
causing the apparent improvement.
Also, keep in mind that MCP bracket pulsing is very much slower than photocathodegating. Even though the bracket timing is controlled automatically by the software, in anexperiment where it is necessary to delay the arrival of the laser pulse at the sample, thisChapter 7

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87will mean inserting an additional delay of 500 ns to accomplish coincidence at the detector.
MCP bracketing should only be used in experiments where it is going to make a difference.
Note that background light need not be the limiting factor in measurements where MCP
bracket pulsing is unable to provide the required degree of rejection. In suchmeasurements, the option remains of installing an external shutter ahead of the PI-MAX.

Impact of Bracket Pulsing on Delay
If operating in the UV when bracket pulsing is activated (Gen II Intensifier only), the MCP
gate automatically brackets the photocathode gate pulse to further enhance the on/off ratio.
There is, however, a limitation of bracket pulsing that can complicate the coincidence ofthe signal and gate at the camera. Because MCP bracket gating is much slower thanphotocathode gating (500 ns is required to gate the MCP on and another 200 ns to gate the
MCP off at the end of the photocathode gate). As a result, MCP bracket pulsing should not
be used in experiments where the delay between the trigger and the photocathode gate isless than 1 µs.
Note: The 1 µs restriction does not apply when you are using a PTG with Anticipatormode selected or when you are using a PTG, a pre-trigger is available, and the PreTrigger mode is selected.

Setup
MCP Bracket pulse implementation in a system having a PTG is accomplished by
selecting Bracket Pulsing ON from the host software and selecting the Bracket Start
parameter appropriate to your experiment (see choices below). The Timing Gen cable
carries the signal that gates the MCP on and off if bracket pulsing has been turned on.
Figure 35, page 88, is a timing diagram for a PTG that has been set up for bracket pulsing
with a "Main" bracket start. Note that the insertion delay is 25 ns instead of the 85 ns
insertion delay characteristic to the DG535.
The four Bracket Start choices are:

Main: Main times the bracket start from the main trigger (either an external or aninternal trigger). Select this if the event of interest will occur at least 1 µs after
the main trigger (the 1 µs includes the 500 ns required to turn the MCP fully on).



Main+Burst: Select this if Burst mode is active. Brackets an entire burst but not
the individual pulses within a burst.



Pre-Trigger: Allows you to capture an event that would otherwise occur while
the MCP was turning on. This selection requires that, in addition to the main
trigger at Ext Trig In, you trigger the PTG by a pulse applied to the Pre-Trig In
BNC. The pre-trigger must be at least 525 ns before the main trigger. After an
insertion delay of approximately 25 ns, the MCP will be gated on before the main
trigger occurs. The main trigger plus the gate delay and width parameters
determine the photocathode gating and the MCP turn off. Because the MCP isgated on earlier, it is on for a longer period of time and therefore there is a slight
loss of on/off ratio. However, you would be able to capture a non-repetitive
event.



Anticipator: Select this if the experiment is repetitive, driven by an external
trigger at a constant frequency, and the event of interest would occur before the
MCP has fully turned on. It is critical that the trigger pulse be as jitter free as
possible, since the anticipator circuit will look at the pulse repetition rate (for the

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first pulse to pulse period), and then anticipate each of the subsequent external
triggers in the series. In this way, the bracketing pulse is timed to lead thephotocathode gate pulse by the anticipate time entered in the Anticipate By field.
The on/off ratio in the UV is retained.
For proper operation, the bracketing pulse must begin at least 500 ns before thegate pulse. The minimum Anticipator Time is 500 ns (or the minimum PI-MAX
bracket lead-time from EEPROM) minus the minimum Gate Delay time. For
example, with a minimum Gate Delay time of 200 ns, the minimum Anticipatortime would be 300 ns.
Note: Because Gen III Intensifiers do not respond in the UV, bracket pulsing is notavailable for these intensifiers.

Figure 35. PI-MAX Timing for MCP Bracket Pulsing with PTG Timing Generator

MCP Gating
Introduction
MCP gating is only available with the PI-MAXMG system. This gating mode (not to be
confused with MCP bracket pulsing) provides you with a unique combination ofnanosecond-scale gating speed and high ultraviolet QE. Normally, such high UV QE isonly available in so-called slow gate intensifiers (i.e., those without a nickel underlay).
The PI-MAXMG applies the primary gating pulse to the MCP portion of the tube and, if
chosen by the user, applies the bracket pulse to the photocathode. Consequently, it
provides the full benefit of bracket pulsing along with enhanced QE.
The main limitations with this option are that there is a somewhat larger propagation
delay and larger optical FWHM than a standard fast gate PI-MAX. Quantitatively, thepropagation delay of the PI-MAX itself is in the 40 ns range compared to 10-12 ns for astandard PI-MAX. Note that the PTG propagation delay is in addition to the 40 ns.
Minimum FWHM for a PI-MAXMG system is in the 8 to 15 ns range, compared to 1.5 ns
to 2 ns for a standard PI-MAX. Pulse repetition rate is limited to 1 kHz.

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Setup and Operation
The PI-MAXMG is set up in the same way as a standard PI-MAX and is compatible with
the PTG (preferred) and the DG535 timing generators. Note that with a PTG, a width
setting of 37 ns produces a gate width of 37 ns because the gate width selected with the
PTG is the optical FWHM.
1. Start with Shutter Mode operation if possible, to get initial operation, focus, etc.
(see Chapter 4, First Light).
2. Then, switch to Gate Mode and a relatively long gate to acquire the phenomenon ofinterest.
3. Finally, narrow down the gate to the desired operation.
When possible in the experiment, it is a good idea to use bracket pulsing to limit thephotocathode ON time. The required “lead time” or pretrigger time for the photocathodebracket pulse is 300 ns (compared to 500 ns for a standard PI-MAX MCP bracket pulse).
Note: Pulse repetition rate is limited to 1 kHz.

Gain Variation
MCP gain approximately doubles for each 50 V increase in voltage. Therefore, small
ripples in the MCP voltage as a result of the gating waveform will cause gain changes
that vary with time after the rising edge of the gate pulse. A gain overshoot of 20 to 30%
during the first 20 ns of a gate pulse is typical, with smaller variations later in time if awider gate pulse is used. For a given gain setting and pulse width, these variations arereasonably repeatable, and may be calibrated.

Fluorescence Experiment
A typical laser-induced fluorescence experiment might incorporate a pulsed laser that
excites a sample with the laser beam and that additionally provides a trigger to the PTG.
When the laser pulse hits the sample, some atoms are raised to a higher energy state andthen spontaneously relax to the ground state, emitting photons as they do to generate thefluorescence signal. This signal can be applied to a spectrograph that spreads thefluorescence spectrum across the photocathode of the PI-MAX. The spectrum would thenbe intensified and applied to the PI-MAX’s CCD array.

Cabling for MCP Gated Operation
Figure 36 illustrates the cabling for an MCP gated experiment using a PTG*. The laser
trigger output is applied to the Ext. Trig. In connector of the PTG to initiate the timing
sequence. The Start/Stop outputs of the PTG are applied to the PI-MAX via the Timing
Gen cable to gate the MCP on and off. This cable also carries the signal that gates thephotocathode on and off if bracket pulsing has been selected. Another timing generator
output is fed through the back plane to inhibit readout while the timing generator is busy.
Finally, to prevent artifacts from the laser from degrading the data, it is essential that thetiming generator be inhibited during each readout. The handshake for this inhibiting
function is also routed through the backplane. The PTG parameters are set from thecomputer by the application software.
Other system cabling would include the Detector-Controller cable that interconnects the
PI-MAX and the controller and the TAXI cable between the controller and the computer.
* Requires ver 2.4 or later WinView/32 or WinSpec/32 software.

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Figure 36. MCP Gated Operation Cabling

Figure 37 is a timing diagram for a PTG. Note that the insertion delay is 25 ns instead of
the 85 ns insertion delay characteristic to the DG535.

Figure 37. PI-MAX Timing in MCP Gated Operation with PTG Timing Generator

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500 ps Gating Option
The 500 ps Gating Option, available for PI-MAX detectors with fast gate RB
intensifiers, uses the PTG for timing. Please refer to the following
information when in setting up your system for this option:
1. Enable the 500 ps
gating option by
selecting the "Enable
Fast Pulse Option"
checkbox on theExperiment
Setup|Main tab (seeFigure 38). Wait
about 10 minutes
before taking data toensure that theacquired data will bevalid.

Figure 38. Experiment Setup|Main tab

2. When setting up thepulser, select the
PTG as the active
pulser.
3. When setting up
triggers, themaximum trigger
frequency is 2000 Hz.

Figure 39. PTG|Triggers tab

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4. After setting thetrigger frequency, set
the gating
parameters. Whenthe 500 ps option isenabled, you will see"2 ns Board Is
Enabled" on thegating setup dialogs(for example, on the
Repetitive Gating
dialog in Figure 40).

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Figure 40. Repetitive Gating dialog

5. Before taking data, verify that about 10 minutes has elapsed since you
enabled the Fast Pulse Option. This will ensure that the acquired data will
be valid.

Additional Experiments
Introduction

Figure 41. Experiments with the PI-MAX

Figure 41 illustrates the kinds of experiments that can be performed with a PI-MAX
detector and PTG. Of the many gated measurements that can be performed with a
PI-MAX and PTG, most will fall in one of the following categories:

Static Gate: This type of experiment may also be referred to as “RepetitiveContinuous”. There is a repetitive trigger, and the Gate Width and Gate Delay are
fixed. Some variable in the experiment such as pressure, concentration, wavelength
or temperature is varied.



Swept Gate: In this type of experiment, Gate Width, Gate Delay, or both may bevaried.

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Repetitive-Sequential 1: The Trigger is repetitive, Gate Width is fixed, and Delay isvaried over the course of the measurement. The result of the experiment is a plot of
intensity vs. time, such as might be obtained with a sampling oscilloscope. This technique
is used to measure lifetime decays.
Repetitive-Sequential 2: The Trigger is repetitive and Gate Width and Delay arevaried over the course of the measurement. Gate Width and Delay can beincremented in a linear fashion or in an exponential fashion. Increasing the Gate
Width is useful for trying to find fine detail in a weak decaying signal. If you choose
linear, you have to take a lot more points. Exponential lets you take data points closer
together where the signal is changing rapidly and further apart where the signal ischanging slowly.
Single Shot: A single shot experiment is one where you have only one chance to catchthe data. Any experiment that can’t be repeated more often than once a minute, such as
high power lasers and explosives, is considered a single shot. You have to catch thetrigger when it comes. Prior to the event, the CCD runs in continuous cleans mode. You
don’t have the luxury of having the CCD just sitting there doing nothing because the
CCD will be accumulating dark current. When the trigger arrives, the intensifier gates,
the continuous cleans stop, and the array is read out with a minimum of dark current.

The next section provides step-by-step instructions, along with diagrams and screen
shots, for setting up and performing a Swept Gate experiment with fixed Gate Width andvariable Gate Delay (type Repetitive-Sequential 1).

Procedure for Setting up and Performing a Swept Gate Experiment(Fixed Width, Variable Delay)
This experiment is an attempt to time-resolve a Xenon light flash from a commerciallyavailable strobe light. Since the strobe does not have a "pretrigger" out, an electrical
trigger is generated by using a photodiode. Output from the photodiode is connected to
the Ext. Trig. BNC of the PTG (Figure 42). Then perform the steps that follow.

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Figure 42. Experiment is Master Clock: Hardware Setup and Timing DiagramChapter 7

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Experiment as Master Clock
The following procedure uses the experiment as the master clock and therefore refers toconnections as shown in Figure 42.
1. Switch on the equipment and start the WinX application software (Ver. 2.4 andhigher).
2. Choose the appropriate camera/controller in the Setup|Hardware|Hardware
Setup dialog. The screen should resemble Figure 43, which shows the setup fora Thomson 512 x 512 full frame camera.
a. Choose High Speed PCI or PCI (Timer) on the Interface tab and enter the
I/O Address and the Interrupt Level, if appropriate. See Figure 43.

Figure 43. Hardware Setup: Controller/ Camera and Interface tabsb. Click on “Load Default Values” on the Cleans/Skips tab.
c. Set the detector temperature by selecting "Detector Temperature" on the
Setup menu, entering the Target Temperature information, clicking on "Set
Temp" and then clicking on "OK". You may want to refer to theWinView/32 or WinSpec/32 manual, as appropriate.
3. If you have a spectrograph, set the spectrograph properties by using the menu
items on the "Spectrograph" menu (WinSpec/32 only). If the spectrograph you
will be using has not been installed, first click on "Install/Remove Spectrograph"and do so before setting the properties. Figure 44 shows the WinSpec/32
sequence for an Action 300I spectrograph.

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2.

3.

Figure 44. Define Spectrograph and Install/Remove Spectrographs dialogs

4. After you have installed and defined the spectrograph, move the grating to thedesired wavelength.

Figure 45. Move Spectrograph dialog

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5. At this point, it is a good practice to make sure that the camera is focused byrunning it in Free Run mode. This requires that you set the experiment parameterson the Experiment Setup tabs (refer to Figure 46 and Figure 47). On theExperiment Setup|Main tab, choose Shutter Mode, set a value between 0 and
255 for MCP gain, and set the appropriate integration time. On the Timing tab,select Free Run and Fast Mode. On the ADC tab, select the appropriate ADC
type. On the ROI Setup tab, select the appropriate ROI.

Figure 46. Experiment Setup: Main and Timing tabs

Figure 47. Experiment Setup: ADC and ROI Setup tabs

6. Because there is a risk of overloading the camera in Shutter Mode, make surethat the room or ambient illumination is low (i.e., you have difficulty seeing in
the room).

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7. After setting the parameters and making sure the ambient light level is low, clickon Focus.
8. If the readout mode is currently set to “Use Region of Interest” on the Main tab,the camera will start acquiring data immediately. If the readout mode is currently
set to “Use Full Chip” you will be asked if you want to change the setting to“Use Region of Interest” before focus mode is activated. Click on “Yes” and thecamera will begin acquiring data.
9. After you make sure that the camera is seeing in Free Run mode, stop dataacquisition.
10. Set up the pulser (PTG). The following figures show typical examples of thescreens you would use to set up the PTG.
a.

After selecting the PTG as the active pulser, click on "Setup PTG…".
Define the external trigger on the Triggers tab. See Figure 48.

b.

On the Gating tab, select Sequential as the Active Mode and then click on"Setup…". For this experiment both Burstmode and Bracket Pulsing are
OFF. See Figure 48.
Note: The Gate Delay From: choice will only appear if you have checked"Use NVRAM Calibration (if present)" on the Get/Set Parameter and the
PTG Get/Set Parameter dialogs (accessed from the Diagnostics menu). The
NVRAM calibration is the factory calibration and will give you the mostaccurate timing information gate width and delay.

Figure 48. PTG: Triggers and Gating tabsc.

Click on "Setup…" and define the pulse sequence on the Sequential Gating
Setup dialog. See Figure 49.
Enter the number of spectra to be acquired (in this case, 41).



Select "Fixed Increment".

Enter the start and end times for the gate width. (Since this experimentrequires a fixed gate width these values will be the same.)Enter the start and end durations for the gate delay. (For this experiment,
the start delay is 1 µs and the end delay is 201 µs.) Note that theminimum gate delay for T0 is 1.5625 ns.

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Then select the number of exposures (in this case, 1 exposure).

To check the gate delay for each of the 41 spectra, click on "View
Width/Delay Sequence."

99

Figure 49. Sequential Gating Setup and Width/Delay Sequence dialogsd.

If you are using the Aux. Trig. Out signal from the PTG to trigger a piece ofequipment, then enter the Auxiliary Trigger Out delay time on the Aux.
Trig. Out tab. See Figure 50.

Figure 50. Aux. Trig. Out tabe.

Click on OK to program the pulser/timing generator.

11. Set up the experiment parameters from the Experiment Setup dialog.
a.

On the Timing tab, change the timing as shown in Figure 51.

b.

On the Main tab, enter the exposure time, gain and switch to Gate Mode.
The number of spectra will be automatically set depending on the number
entered on the Sequential Gating Setup dialog (Figure 49).

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Figure 51. Experiment Setup: Timing and Main tabs

Note: In Gate Mode, the photocathode is biased on only for the time that eachgate pulse is applied. As a result, the tolerance to room light is higher in gatedoperation than it is in Shutter Mode, but the risk of damaging overload from
intense light sources such as lasers remains.
12. After verifying all connections and equipment readiness, click on Acquire to
begin acquiring the spectra (or images).
13. Figure 52 displays the 3-D graph for a “Sequential-Repetitive" experiment with
Fixed Width and Variable Delay (as set in Figure 48 and Figure 49).

Figure 52. Experiment Results in 3-D

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PTG as Master ClockIf you have a light source that has a "Trigger In", the PTG can be used as the Masterclock (cable connections shown in Figure 53). The setup procedure is much the same asthat given for the "Experiment as Master Clock". The differences are that a cable isconnected between the PTG's T0 BNC and the light source (experiment) for triggering
the event and that the 25 ns propagation delay for the External Trigger is no longer afactor.

Figure 53. PTG is Master Clock: Hardware Setup and Timing Diagram

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Procedure for Setting up and Performing a Single Shot Experiment
A single shot experiment offers only one chance to capture an event. As in any gatedexperiment, the "time budget" of the experiment is crucial. If there is no pre-trigger fromthe experiment, a photodiode can be used to generate an electrical trigger from the laser
light. In this situation, light has to be delayed by optical means (fiber-optic cable or
mirror reflections) to allow sufficient time for the electronics to be activated after
receiving the trigger. Another important thing to note in single shot experiments is that
the CCD is set in "Continuous Cleans" mode so that there is no dark charge accumulation
while it is waiting for the trigger.
The following experiment is an attempt to capture a 60 ns fluorescence generated by asingle shot laser. The time budget of the experiment is shown in Table 6 below. This
information is important in order to choose the correct length fiber-optic cable.
Delay Source
Photodiode (light -> TTL pulse)
Photodiode -> PTG (2 ft BNC cable)
PTG
PTG -> PI-MAX (6 ft cable)
PI-MAX

Delay
(ns)
2
3
25
10
15

Total Delay(ns)

Fiber-Optic Cable
Length55

A minimum of 38 ft
of fiber-optic cable isrequired.

Table 6. Single Shot Experiment Time Budget

In this experiment, the cables are kept as short as possible to minimize the length of thefiber-optic cable required.

Figure 54. Single Shot: Hardware Setup

After setting up the appropriate hardware, as shown in Figure 54, default values for"Cleans and Skips" are loaded (Figure 55). If the CCD has to wait more than a few
seconds for the external trigger, it is advisable to increase the number of cleans.

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Figure 55. Cleans and Skips: Default Values Loaded

The sequence of operations is similar to the "Sequential" experiments. After focusing thecamera on the fluorescing sample, the camera is set in "Gate" mode and the appropriate
Gain is selected (Figure 56).

Figure 56. Experiment Setup: Gain Selected

Gate width and gate delay are set in such a way that the intensifier is gated ON during theentire event (in this case the event is a 60 ns fluorescence).

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Figure 57. Repetitive Gating Setup: 100 ns Width, 10 ns Delay

Figure 58 shows the result of the experiment. Figure 59 shows the peak obtained bybinning, in the vertical direction, the entire region around the fluorescence spot.

Figure 58. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay

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Procedure for Setting up and Performing a Swept Gate Experiment(Variable Width, Variable Delay):
The sequence of steps for a Swept Gate experiment with variable width and delay issimilar to the Swept Gate experiment with fixed width and variable delay but with thefollowing exception:

In addition to entering differing start and end values for the Gate Delay, you would
also enter differing start and end values for the Gate Width.

Procedure for Setting up and Performing a Static Gate Experiment(Fixed Width, Fixed Delay)
The sequence of steps for a Static Gate experiment is similar to the Swept Gate
experiment but with the following exceptions:

The Active Mode, selected in Step 10b, would be Repetitive.



The Gate Width and Gate Delay values would be entered in the dialog shown below.
Note that the minimum gate delay from T0 is 1.5625 ns:

Figure 60. Repetitive Gating Setup dialog

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Chapter 8
Gated Operation with a DG535
An Inhibit option must be installed in the DG535 before it can be used to for gating the
PI-MAX. Contact Princeton Instruments Customer Support for information on how to
install/enable the DG535 Inhibit function.

Introduction
This chapter discusses gated operation with a DG535 timing generator and aspects ofoperation of the PI-MAX not covered in Chapter 4, First Light. We additionally suggestthat you review Chapter 11, Tips and Tricks, which contains information that should
prove helpful in getting good results in more complex measurements.
Gate Mode operation is more complex than Shutter Mode operation because of theadditional cabling and timing considerations that apply. However, it is in gated operationthat the PI-MAX achieves its maximum power and utility, able to recover extremely faintfast signals in the presence of large ambient light levels.

Gating provides electronic shutter action by controlling the photocathode bias, allowing
the detection of low light level signals in the presence of interfering light sources of muchgreater energy. For instance, in combustion research, a pulsed laser probe is used toinvestigate the chemistry within a flame. Since the flame itself emits broadband light
continuously, the integrated flame emission is much greater than the integrated signal
resulting shortly after the laser probe (such as laser-induced fluorescence or Raman).
Fortunately, since the laser pulse is very short and the time at which it occurs is known, it
is possible to gate for a few nanoseconds during the laser pulse, thus reducing the flame
emission interference by approximately the measurement duty factor ratio.
Exposure time is the 'time space' from which charge integrating on the CCD will get
summed into the reported data. Gate width is the time during which light will be detectedby the intensifier, intensified, and applied to the CCD. Basically, the intensifier controls
what the chip 'sees' during the exposure time.
For signal to be detected, it must both fall in a valid gate width and in a valid exposure
time. Many gate pulses can be placed into one exposure time at random intervals because
there is no temporal measure inside a given exposure (all incident signals get summed(integrated) into one value per pixel / superpixel inside a given exposure).
Using presently available image intensifiers and gate pulse generators, optical gate times
 2 ns FWHM (full width at half maximum) are possible. Since the control is electronic,
the gate width can be made virtually as long as desired, allowing a wide range ofexperiment requirements to be satisfied in one instrument setup. Further, in UV
measurements, where the On:Off ratio is only 104:1, the PI-MAX’s MCP bracketingfeature can be used to extend the On:Off ratio to 106:1.

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Precautionary Measures
WARNING

Intensified CCD detectors, such as the PI-MAX, when biased ON, can be irreparably
damaged if continuously exposed to light levels higher than twice the A/D saturationlevel. Thus it is critical that you not establish conditions that could result in damage tothe intensifier. Although intensified detectors are less prone to damage from backgroundlight when operated gated, they are at significant risk of damage from high-intensity lightsources such as lasers. High intensity sources can damage the intensifier before theprotection circuits have time to respond, or even cause spot damage without theprotection circuits acting at all. In Shutter Mode operation, it will be necessary to keep
the lab lighting be subdued when working with an intensified detector. If a sustained
alarm indication occurs when the controller is turned on, either completely cover theintensifier to reduce the light to halt the overload condition, or reduce the laboratory
illumination still further until safe operating conditions are established.

Intensifier Modes and Safety
The Experiment Setup Main screen allows selection of three modes, Shutter Mode,
Gate Mode and Safe Mode. In Shutter Mode operation, the photocathode is biased oncontinuously during the exposure time and the room illumination must be subdued toprevent an overload alarm from occurring. In Gate Mode, the photocathode is biased on
only during the time each gate pulse* is applied. As a result, the tolerance to room light ishigher in gated operation, but the risk of damaging overload from intense light sources
such as lasers remains. Intense light sources in gated experiments can cause spot damage
that would be undetected by the alarm circuit. In Safe Mode, the photocathode iscontinuously biased OFF and the intensifier is as safe as it can be.

Alarm
To reduce the risk of detector damage, the PI-MAX detector is equipped with an audible
alarm in the detector head, activated when the intensity of light falling on the image
intensifier exceeds a preset threshold. While the alarm is sounding, the photocathode isdisabled. Immediately toggle the MCP On/Off switch (on the back of the PI-MAX) to
the OFF position. Cover the detector window and only switch the MCP On/Off switch
to ON after the illumination level has been lowered. If the alarm sounds continuously
even when the illumination level is adequately low, shut the system down and contact thefactory for guidance.
Note: It is normal for the alarm to sound briefly when the system is turned on.

CautionDiscontinue operation and contact the factory at once if sporadic or continuous
unwarranted alarms occur. They may indicate intensifier damage or another situation that
requires immediate attention.

* The Gate pulse is produced inside the PI-MAX from the Start and Stop signals supplied by the

Timing Generator.

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DG-535 and Gate Mode Overview
For gate mode operation with a DG535 Timing Generator, External Sync with PreOpen
timing must be selected (Acquisition|Experiment Setup…|Timing tab). A "frame
cycle" is initiated by the D output of the DG535 that must be applied to the Ext Sync
input of the ST-133. Without this connection and mode selection, an exposure andreadout cannot occur.
A frame cycle consists of an “exposure” followed by a readout. The “exposure” defines
the time “space” in which the data gets collected. If, as is generally the case, you want thereadout to begin as soon as possible after Ext Sync is applied, set the Exposure Time
to Zero and the Shutter Type (WinView/32 or WinSpec/32 Hardware Setup) to None(the latter setting removes the shutter compensation time, another source of delay).
The Accumulations and Images parameters (Acquisition|Experiment
Setup…|Main tab) govern how the data will be processed and whether any given Ext
Sync signal will initiate a controller cycle or be ignored. Integrating multiple events on
the CCD really brings the power of the PI-MAX to bear on low-light gate-mode
experiments. If the experiment allows, many pulses can be summed on the CCD with nopulse artifacts in the readout. The signal increases nearly linearly with the number ofpulses (within limits imposed by the CCD).
Examples:1. If you want to acquire 5 separate images, set the ET=0, Number of Images (orSpectra)=5, and Accumulations=1.
2. If you want to acquire single image that is the sum of integration during 5 gate
pulses, set the ET so that it is long enough to encompass 5 gate pulses, Numberof Images (or Spectra)=1, and Accumulations=1.

Timing Modes
The Timing mode determines when and how the data will be read out. Table 7 shows thepossible Timing Mode and Shutter Control combinations when operating in Gate Mode.
As shown in the table, the following timing modes are available: External Sync andExternal Sync with Continuous Cleans.
Timing Mode

"Shutter" Control Ext Trigger Input

External Sync

PreOpenExt Sync BNC

External Sync with Continuous Cleans

PreOpenExt Sync BNC

Table 7. Timing Mode, Shutter Control, and Ext. Trigger Input
when a DG535 is the Timing Generator

External Sync
External synchronization uses the External Sync trigger from the DG535's D output todetermine when the data is readout of the array (Exposure Time = 0 s.) or when the
exposure time will begin (Exposure Time > 0 s.). Because of pulser constraints, External
Sync mode must always be used with the PreOpen shutter mode, which ensures that the
DG535 is not "Inhibited" from gating the photocathode while the array is ready tointegrate signal.

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The timing diagrams below show the sequence of events for a 0 second exposure timeand for an exposure time greater than 0 seconds. When the exposure time is set to 0
seconds (Acquisition|Experiment Setup…|Main) and External Sync PreOpen is
selected, the gating determines the actual time (texp) that the array will be exposed toincoming signal.

Figure 61. DG535: External Sync, PreOpen, Exposure Time = 0 s.

When the exposure time is set to something other than 0 (Acquisition|Experiment
Setup…|Main) and External Sync PreOpen is selected, the start of the exposure time iscontrolled by the External Sync trigger, and one or more gates may occur during theexposure time depending on the gating parameters set up for the DG535(Setup|Pulsers…|DG535).

Figure 62. DG535: External Sync, PreOpen, Exposure Time > 0 s.

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External Sync with Continuous Cleans
External synchronization can also use a function called Continuous Cleans (represented
by CC in the figure below). In addition to the standard “cleaning” of the array, which
occurs after the controller is enabled, Continuous Cleans will remove any charge that
integrates on the array after the Start Acquisition command has been sent to the ST-133
until the moment the External Sync pulse is received. As mentioned earlier in the manual,values continuous cleans are entered on the Setup|Hardware …|Cleans/Skips tab. If
the CCD has to wait more than a few seconds for the external trigger, it is advisable toincrease the number of cleans.

Figure 63. DG535: External Sync, PreOpen, Cont. Cleans, Exposure Time > 0 s.

DG535 Gating Setup
In the WinX application, trigger, gating, and communication port parameters for the
DG535 are defined via the Setup|Pulsers|DG535 dialog. The Triggers tab card allows
you to indicate whether the DG535 will use an internal trigger (occurring at X frequency)
to initiate an Ext. Sync trigger from its D output or whether the trigger source will be asignal input at its Trig IN input.

Figure 64. DG535 Triggers tab

Gating parameters are set up via the Gating tab card and via the Repetitive Gating Setup
and Sequential Gating Setup dialogs that are accessed from this tab card. With repetitive

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gating the gate width and gate delay are constant for the specified number of exposures.
With sequential gating either or both gate width and gate delay change as images orspectra are acquired.

Figure 65. DG535 Gating tab

Figure 66. DG535 Repetitive Gating
Setup dialog

Figure 67. DG535 Sequential Gating Setup dialog

The DG535 parameters for communicating with the host computer are set up or changedon the Comm Port tab card. Select GPIB for the port type and select the port address.
The Port address setting determines which GPIB address the computer will use incommunications with the DG535 Pulser. Selections include 1 through 30 plus Demo,
which allows the DG535 software routines to be exercised even though a DG535 is notconnected. The selected address must match the one selected at the DG535 and thedefault value is 15. After you select the correct COM port, click on the Initialize Port
button to initialize it.

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Figure 68. DG535 Comm Port tab

Fast Gating
A particularly noteworthy feature of the PI-MAX is its ability to gate in as little as 2 ns orless when the PI-MAX has been configured with a fast gate intensifier. The camera’s
exceptional gating performance can be easily demonstrated with a straightforward
experimental setup.
The following fast-gated experiment was
performed using the PI-MAX camera with the
fast-gate option and operated in conjunction with
Princeton Instruments’ WinSpec/32 software, aHamamatsu PL0-01 Picosecond Light Source,
and a DG535). Other equipment included a
computer and an ST-133 Controller. To do theexperiment, 60 ps pulses from the Hamamatsu
Light Source triggered from the timing generator
were applied to the PI-MAX and a gatedmeasurement was performed.

Sequential Gating Setup
Number of Spectra: 61
Start Gate Width: 2 ns
End Gate Width: 2 ns
Start Gate Delay: 102 ns
End Gate Delay: 105 ns
Increment Type: Fixed
Delay Increment: 0.05 ns

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Figure 69. DG535 Fast Gating Experiment Block Diagram

In both setups, the WinSpec/32 software’s sequential gating function was used toincrement the delay to the PI-MAX gate in 50 ps steps. As a result, with respect to theapplied light pulses, the PI-MAX was gated 50 ps later with each repetition. The datafrom each pulse was collected and displayed in a 3-D plot with time on the Z axis. By
sliding the coincidence time of the gate and applied light pulses in this manner, a plot was
produced that accurately characterized the temporal profile of the PI-MAX fast gatefunction. The measurement results are shown below. FWHM on the gate was 1.6 ns andthe FW was measured at 2 ns.

Figure 70. Fast Gating Measurement Results

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MCP Bracket Pulsing
Introduction
The principal utility of gating is that it allows temporal discrimination against backgroundlight. By allowing the photocathode to “see” only during the event of interest, very highbackground illumination levels can be tolerated without materially degrading experimentresults. The limit on this technique is set by the light leakage of the intensifier, which,although it is very good, is not without limit. In the visible, the on/off ratio of a typical Gen II
Intensifier with just the photocathode gated is excellent, typically between 106 and 107. In
most measurements, this ratio is sufficient to assure that the signal reaching the CCD during
the intensifier Off times will be too small to affect the data.
Below 350 nm, however, a second leakage mechanism occurs, optical leakage throughthe photocathode to the UV-sensitive MCP, which reduces the On:Off ratio to about 2 ×
104 at 200 nm. This is the dominant response of a Gen II image intensifier to UV photons
when the photocathode is electrically off. At an On:Off ratio of 20,000, the ability of acamera with conventional photocathode (only) gating to perform certain kinds ofmeasurements in the UV is adversely affected.
MCP bracket pulsing* keeps the MCP biased OFF except for an interval that brackets thetiming of the photocathode gate as shown in Figure 71. For emitted photoelectrons to beaccelerated in the MCP, the MCP must be biased ON. In conventional intensified
cameras, the MCP is biased ON continuously. In the PI-MAX, however, when bracket
pulsing is ON, the MCP is biased OFF until just before the photocathode is gated ON.
The MCP is then biased ON and remains biased ON until just after the photocathode isbiased OFF.

Figure 71. Timing: Bracket Pulsing

Traditionally, intensified detectors discriminated against background signal by gating thephotocathode. Although this technique yields very high peak Off/On ratios, on the orderof 5 × 106:1 in the visible, background signal can still prove troublesome in low-duty
factor measurements, particularly in the UV region where the rejection is only ~104 :1.
By bracket pulsing the MCP off (in addition to photocathode gating), the on/off ratio of
the PI-MAX in UV is improved by 2-3 orders of magnitude. The resulting UV ratio
exceeds even the high levels normally achieved in the visible. Applications that benefit
from this new approach include LIF and nanosecond pump-probe experiments.
Note: Bracket pulsing does not help in the visible region. Under extremely low dutyfactor conditions, the only remedy is to install an external shutter ahead of the camera.

*

Bracket pulsing is not available for cameras having a Gen III Intensifier. Gen III Intensifiers do
not respond in the UV.

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Bracket Pulsing in LIF Measurements
Most experiments using laser-induced fluorescence to probe combustion flows are
performed with UV probe/lasers. Atomic emission from flames also has significant UVcontent. If the flame is continuous, the UV background will also be continuous. Even
where a flame is transient (e.g. internal combustion engine), its lifetime can be many ms,
compared to the nanosecond time scale of the laser used. This background can be amillion times as long. If the background is bright, then a UV on/off ratio of 20,000:1 will
be overwhelmed by the duty cycle and not adequate for extracting a signal of 10-5. In highdynamic range quantitative measurements, backgrounds must be kept to an absolute
minimum. MCP bracket pulse gating dramatically improves the rejection of CW andeven ms time-scale background.
An alternative to suppressing background for imaging has been the use of very narrowspectral bandpass filters. In the UV, these filters are expensive and they can have lowtransmission at their central wavelength. An additional filter is required for eachwavelength to be imaged. The use of electronic temporal rejection of CW or quasi-CW
background may make it unnecessary to use these filters, thus increasing the opticalthroughput, sensitivity, and quantitative precision of the measurement.

Bracket Pulsing in Nanosecond Pump Probe Experiments
Some nanosecond pump-probe experiments combine a nanosecond or faster pump with aflashlamp probe. The duration of the probe flash can be 10-50 µs and a gate is used to
select the specific nanosecond-scale time slice to be observed within the much longer
probe flash. In these absorbance experiments, accurate measurement of absorbancevalues depends critically on the lack of stray light contamination, particularly at moderate
to high optical density levels. Selecting a 5 ns time window out of a 10 µs pulse isalready one part in 2,000. If UV leakage gives an on/off ratio of only 20,000:1,
contamination could be 10% of higher. This would limit the optical density to 1.0, and it
could make linear quantitation difficult beyond 0.1 OD.
MCP bracket pulse gating can substantially improve the on/off ratio in such an
experiment. Even with a 1 µs MCP pulse, the rejection of flash-lamp leakage can add
more than an order of magnitude of range, to 2.0 OD.

Limitations of Bracket Pulse Gating
MCP bracket pulse gating is most useful in rejecting background that lasts microseconds
up to CW. Fast transient backgrounds can be in the form of stray laser light scattering(Raleigh, MIE, Raman) or unwanted fast fluorescence. Because these usually fall below
the MCP bracket pulsing 1 µs delay restriction, these measurements cannot be improved
by MCP bracket pulsing in the PI-MAX.
Electrically, gating the MCP will only reduce leakage at wavelengths where the MCP has
photoelectric response (primarily in the UV). Thus, for visible and NIR wavelengths
where leakage is primarily optical, the improvement will be minimal (although the on/off
ratio is already very good in these regions). Note that in some spectroscopic applications,visible leakage may appear to be reduced by MCP pulsing. This is because the second
order UV spectrum overlays the first order visible spectrum in a grating spectrograph.
MCP pulsing can eliminate unwanted sensitivity to CW or quasi-CW second order UV,
causing the apparent improvement.
Also, keep in mind that MCP bracket pulsing is very much slower than photocathodegating. Even though the bracket timing is controlled automatically by the software, in anexperiment where it is necessary to delay the arrival of the laser pulse at the sample, thisChapter 8

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will mean inserting an additional delay of 500 ns to accomplish coincidence at the detector.
MCP bracketing should only be used in experiments where it is going to make a difference.
Note that background light need not be the limiting factor in measurements where MCP
bracket pulsing is unable to provide the required degree of rejection. In suchmeasurements, the option remains of installing an external shutter ahead of the PI-MAX.

Impact of Bracket Pulsing on Delay
If operating in the UV when bracket pulsing is activated (Gen II Intensifier only), the MCP
gate automatically brackets the photocathode gate pulse to further enhance the on/off ratio.
There is, however, a limitation of bracket pulsing that can complicate the coincidence ofthe signal and gate at the camera. Because MCP bracket gating is much slower thanphotocathode gating (500 ns is required to gate the MCP on and another 200 ns to gate the
MCP off at the end of the photocathode gate). As a result, MCP bracket pulsing should not
be used in experiments where the delay between the trigger and the photocathode gate isless than 1 µs.

Setup
Implementing bracket pulsing involves
selecting the function in software (Figure 72)
and applying the DG535’s
output via
the C+D-Gen II/A+B-Gen III cable to the
PI-MAX Timing Gen connector. The precise
timing required to implement the function is
automatically set according to photocathodegate width and delay, with the limitation thatbracket pulsing should be deselected (or the
C+D-Gen II/A+B-Gen III cable disconnected)
if the delay between the trigger and the gate
pulse is less than 1 µs. This limit is imposed by
the relatively slow on/off time of the bracket
pulse function. It takes 500 ns to gate the
MCP on and another 200 ns to gate it off.

Figure 72. Gating tab

Note: Because Gen III Intensifiers do not respond in the UV, bracket pulsing is notavailable for these intensifiers.

MCP Gating
Introduction
MCP gating is only available with the PI-MAXMG system. This gating mode (not to be
confused with MCP bracket pulsing) provides you with a unique combination ofnanosecond-scale gating speed and high ultraviolet QE. Normally, such high UV QE isonly available in so-called slow gate intensifiers (i.e., those without a nickel underlay).
The PI-MAXMG applies the primary gating pulse to the MCP portion of the tube and, if
chosen by the user, applies the bracket pulse to the photocathode. Consequently, it
provides the full benefit of bracket pulsing along with enhanced QE.
The main limitations with this option are that there is a somewhat larger propagation
delay and larger optical FWHM than a standard fast gate PI-MAX. Quantitatively, thepropagation delay of the PI-MAX itself is in the 40 ns range compared to 10-12 ns for astandard PI-MAX. Note that DG535 propagation delay is in addition to the 40 ns.

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Minimum FWHM for a PI-MAXMG system is in the 8 to 15 ns range, compared to 1.5 ns
to 2 ns for a standard PI-MAX. Pulse repetition rate is limited to 1 kHz.

Setup and Operation
The PI-MAXMG is set up in the same way as a standard PI-MAX and is compatible with
the DG535 and the PTG (preferred) timing generators. The cables used for a standard
PI-MAX are used for the PI-MAXMG. Note that when using the DG535, the set value ofgate width is significantly larger than the optical FWHM. Typically, a width setting of
37 ns produces a FWHM in the range of 7 to 9 ns.
1. Start with Shutter Mode operation if possible, to verify initial operation, tofocus, etc.
2. Then, switch to Gate Mode and a relatively long gate to acquire thephenomenon of interest.
3. Finally, narrow down the gate to the desired operation.
When possible in the experiment, it is a good idea to use bracket pulsing to limit thephotocathode ON time. The required “lead time” or pretrigger time for the photocathodebracket pulse is 300 ns (compared to 500 ns for a standard PI-MAX MCP bracket pulse).
Note: Pulse repetition rate is limited to 1 kHz.

Gain Variation
MCP gain approximately doubles for each 50 V increase in voltage. Therefore, small
ripples in the MCP voltage as a result of the gating waveform will cause gain changes
that vary with time after the rising edge of the gate pulse. A gain overshoot of 20 to 30%
during the first 20 ns of a gate pulse is typical, with smaller variations later in time if awider gate pulse is used. For a given gain setting and pulse width, these variations arereasonably repeatable, and may be calibrated.

Fluorescence Experiment
A typical laser-induced fluorescence experiment might incorporate a pulsed laser that
excites a sample with the laser beam and that additionally provides a trigger to the DG535.
When the laser pulse hits the sample, some atoms are raised to a higher energy state andthen spontaneously relax to the ground state, emitting photons as they do to generate thefluorescence signal. This signal can be applied to a spectrograph that spreads thefluorescence spectrum across the photocathode of the PI-MAX. The spectrum would thenbe intensified and applied to the PI-MAX’s CCD array.

Cabling for MCP Gated Operation
Figure 73 illustrates the cabling for this experiment using a Stanford Research DG535 Timing
Generator. The laser trigger output is applied to the Trig. In connector of the DG535 toinitiate the timing sequence. The A and B edge outputs of the DG535 gate the MCP on andoff. The
pulse output gates the photocathode on and off if bracket pulsing* has been
selected. These three signals, A, B, and, are applied to the PI-MAX Timing Gen
connector. Another timing generator output, D, is applied to the Ext. Sync input of thecontroller to initiate readout. Finally, to prevent artifacts from the laser from degrading* Bracket pulsing is not available for camera’s having a Gen III Intensifier. Also, if the camera has

a Gen III Intensifier, for proper operation, it is theDG535 output that must beconnected to the camera Timing Gen connector and not the
DG535 output.

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the data, it is essential that the timing generator be inhibited during each readout. This isaccomplished by connecting the controller’s Shutter output signal (provided at ST-133’s
output) to the Inhibit input of the DG535. The DG535 parameters are set fromthe computer by the application software.
Other system cabling would include the Detector-Controller cable that interconnects the
PI-MAX and the controller, the TAXI cable between the controller and the computer, and
the GPIB link between the computer and the DG535.

Figure 73. MCP Gated Operation Cabling

Figure 74 is a timing diagram for a DG535. A diagram of the PTG timing would be
similar, the principal difference being that the insertion delay would be 25 ns instead of
the 85 ns insertion delay characteristic to the DG535.

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Figure 74. PI-MAX Timing in MCP Gated Operation with DG535 Timing Generator

Chapter 9
Kinetics Operation
Notes:
1. Kinetics operation requires that the Kinetics option has been installed in theController. If the communication protocol is USB 2.0, kinetics operation is
supported by WinView/WinSpec Version 2.5.18.1 or higher.
2. Kinetics operation is not supported by Interline CCDs (PI-MAX2:1003).

Introduction
Charge can be shifted on the surface of a CCD array much faster than it can be read out.
If only a small area of a CCD is illuminated, the charge from several exposures can beshifted along the surface, in much the same way that a long strip of film is passed througha traditional photographic camera to record a series of images. Instead of moving thefilm, the camera moves only the charge along the surface of the array, and this makes itvery fast. Refer to "Readout of the Array", beginning on page 60, for more information
about charge shifting and array readout.

Masking
For Kinetics operation, a portion of the photocathode on the intensifier must be masked
so it can be used as a storage area. The masking can be accomplished via a mechanical oran optical mask at the photocathode or entrance slit. (One form of optical masking uses
multiple fiberoptic cables with differing lengths for time delay.) If the open area is small
relative to the storage area, quite a few images can be acquired in rapid succession, forexample with 50 open rows and 256 rows masked, 5 images can be acquired in a total of
approximately 1.2 ms.

Shutter Mode and Kinetics
Introduction
In Shutter Mode, kinetics operation can be run in Free Run, can take a series of images
initiated by a Single Trigger, or can take a single image for each trigger in a series oftriggers.

Free RunIn Free Run Kinetics mode, the ST-133 takes a series of images, each with the exposure
time set through the software, with only a few microseconds between images. The exact
number of images depends on the Window Size you select on the Hardware
Setup|Controller/Camera tab. Window Size is the number of rows allocated for an image
subframe. The number of subframes is the number of pixels perpendicular to the shift register
divided by the Window Size. The time required to shift a subframe under the mask isdetermined by the Vertical Shift rate (specified in s/row) multiplied by the Window Size.
121

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Example: Assuming an array with 512 rows, specifying a Window Size of 32 would
result in 16 subframes.

Figure 75. Kinetics in Shutter Mode: Free Run Timing Diagram

Single Trigger
Single Trigger Kinetics mode takes an entire series of image subframes with each
External Trigger Pulse (applied at the Ext. Sync BNC on the ST-133). When the External
Sync occurs after the Start Acquisition (STARTACQ) command, the photocathode isbiased on for the exposure time set in the software. The photocathode is biased off at theend of the exposure time, and the subframe is shifted. The photocathode is biased on
again and the cycle repeats until the subframes have been acquired. At that point, thephotocathode is biased off, the shutter compensation time elapses, and the CCD is readout at normal speeds. Once the readout is complete the camera is ready for the next set ofsubframes of exposures. The number of subframes in a series is based on the number ofrows on the CCD divided by the Window Size.
Single trigger timing is shown in Figure 76, where a single External trigger pulse is used
to collect a burst of 6 subframes.

Figure 76. Kinetics in Shutter Mode: Single Trigger Timing Diagram

Multiple Trigger
Multiple Trigger Kinetics takes a single image in the series for each External Sync pulse
received by the ST-133. When the first External Sync occurs after the Start Acquisition(STARTACQ) command, the photocathode is biased on for the exposure time set in thesoftware. The photocathode is biased off at the end of the exposure time, the subframe isshifted, and the camera waits for the next pulse to arrive. It then repeats the cycle until allof the subframes have been acquired. At that point, the photocathode is biased off and
CCD frame readout begins. Once the frame has been read out, the camera is ready for the
next series of subframes. The number of subframes in a series is based on the number ofrows on the CCD divided by the Window Size.

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Multiple trigger timing is shown in Figure 77, where a series of 6 subframes is collectedwith 6 External Sync pulses.

Figure 77. Kinetics in Shutter Mode: Multiple Trigger Timing Diagram

Array Readout
Kinetics operation uses the CCD to store a limited number of images in rapid succession.
The time it takes to shift each line on the CCD is as short as a few microseconds,
depending on the CCD. Therefore, the time between images can be as short as a few
hundred microseconds.
Returning to our 4 × 6 CCD example, in this case 2/3 of the array is masked, either
mechanically or optically. The shutter opens to expose a 4 × 2 region. While the shutter
remains open charge is quickly shifted just under the mask, and the exposure repeated.
After a third image is collected the intensifier is gated OFF and the CCD is read out.
Since the CCD can be read out slowly, very high dynamic range is achieved. Shifting andreadout are shown in Figure 78.

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Figure 78. Kinetics Readout

PTG Burst ModeA PTG configured to run in Burst Mode will generate a short burst of very rapid gate
pulses. The pulse burst can be driven from an external trigger or from the internal
oscillator. The maximum number of pulses is duty cycle limited but a good rule of thumbis 50 pulses/burst.
Burst mode is supported in the PI-MAX 512*, 1k, and 1024 RB/SB/UV/HQ models. The
maximum burst mode repetition rate depends on the model and the intensifier. In the1024 series of detectors, the maximum burst repetition rate is 250 kHz (minimum burst
period = 4 µs) For the 512 and 1K series of detectors, the maximum burst repetition ratedepends on the intensifier as in Table 8.

*

Burst mode is not supported in the PI-MAX 512 detectors with Gen II (SB Slow Gate, RB SlowGate) intensifiers.

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Max. Burst Mode
Repetition Rate

Minimum
Burst Period

Minimum
Gate Width

RB Fast Gate

500 kHz

2 µs

>5 ns

SB Fast Gate

500 kHz

2 µs

>5 ns

UV

500 kHz

2 µs

>5 ns

RB Slow Gate

N/A

N/A

N/A

SB Slow Gate

N/A

N/A

N/A

HQ

50 kHz

20 µs

>5 ns

HQ Blue

50 kHz

20 µs

>5 ns

Gen IIGen III

Table 8. Burst Mode Repetition Rate for PI-MAX 512 and PI-MAX 1k Models

One Shot Experiments
One shot experiments can also be performed in the kinetics mode. Two different kinds ofkinetics modes, slow and fast, are provided. In the slow kinetics mode the time scale is on
the order of 10 to 100 µs per image or spectra. In the fast kinetics mode the time scale isin the 2 to 100 ns range. In the slow kinetics case, a small strip on the CCD array is used
for integration of the light signal. The remainder of the array is masked off, either
through the optics or through a physical mask in front of the camera and the masked
portion of the chip is used as its own storage register. The data-acquisition speed islimited by how fast a row of information on the CCD can be physically shifted. For
example, if the vertical shift speed is three microseconds per row and the strip is fiverows tall, it will be possible to get a fresh spectrum every 15 µs. In the case of a chipthat's 256 pixels tall, it will be possible to get 50 spectra on the chip before it iscompletely filled, at which point it can be read out as an image.
In a fast kinetics experiment, a fiber optic delay line can be used to provide the timing.
For example, you might have ten fibers, with the first fiber being 7 ft long, the second
fiber 14 ft long, the third fiber 21 ft long, etc., up to the last fiber, which would be 70 ft
long. The optical delay differences provided by each of those fibers is approximately
10 ns. If the fibers were aligned at the entrance slit of the spectrograph, and gated once,
ten snapshots in time, each one separated from the one above it by 10 ns, would be
produced.

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Gate Mode Experiments - Examples
The combination of PTG and PI-MAX offers numerous possibilities in Kinetics mode.
But in all combinations underlying objective is to synchronize intensifier gate to CCD
shifting and to capture the time resolution of the event on the CCD. Presented below, are
two experiment scenarios that can be carried out with this instrumentation. User is
responsible for masking the intensifier (e.g., through Spectrograph/fiber optic
combination).
Experiment 1: Single Trigger
A single trigger arrives from user's experiment or is internally generated by the PTG. The
PTG generates multiple triggers (burst) based on that trigger. These triggers are used tosynchronize both the intensifier and the CCD shift. Figure 79 is a timing diagram for
Experiment 1.
Hardware Connections
User's trigger pulse connected to Ext. Trig. In of PTG (optional)Aux. Out BNC of PTG connected to Ext. Sync. of ST-133

PTG Settings


Trigger: External or Internal

Pulsing: Continuous with constant Delay and constant Width, Burst Mode
(Number of pulses, period)



AUX:

delay is longer than Gate Width + Delay, but shorter than Burst period

Experiment Setup Settings


Main:



Timing: Single Trigger, +edge, disable Continuous Cleans, Shutter Control isdisabled open.

Gate Mode

Conditions(*



Gate Delay + Gate Width <= AUX delay

Burst period >=AUX delay + shift time*

Number of burst pulses >= Total number of Kinetic shifts

Shift time can be calculated by vertical shift rate and number of rows used in kinetic shifting.
For PI-MAX 1024 vertical shift rate is 30s/row (PI-MAX 512  1.6s/row).
If 10 rows are used in kinetic shift Total shift time = 10*30s = 300s)Chapter 9

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Figure 79. Timing Diagram: Experiment 1

Experiment 2: Multiple Trigger
A trigger, either internal or external, is required for each vertical shift "window" of the
CCD. The PTG generates the gate pulse and an internal sync for each incoming trigger.
The CCD vertical shift is driven by the internal sync of the PTG. Figure 80 is a timing
diagram for Experiment 2.
Hardware Connections
User's trigger pulse connected to Ext. Trig. In of PTG (optional)

PTG Settings


Trigger: External or Internal

Pulsing: Continuous with constant Delay or constant Width

Experiment Setup Settings


Main:



Timing: Multiple Trigger, -edge, disable Continuous Cleans, Shutter Control isdisabled open.

Gate Mode

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Conditions


Gate Delay + Gate Width <= Internal Frequency

Figure 80. Timing Diagram: Experiment 2

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Chapter 10
PI-MAX2 DIF Camera (Double Image Feature)
Introduction
This chapter assumes a basic understanding of the operation of the PI-MAX2 and PTG in
Gate Mode using the WinX application software (WinView/32 or WinSpec/32). Pleaserefer to Chapter 7 of this manual if you do not feel confident with the basic operation of
the PI-MAX and PTG in Gate mode.
The purpose of the PI-MAX2 DIF system is to acquire a pair of gated images in rapid
succession. The time between frames can be as short as 2 µs with exposure times as short
as 5 ns. The DIF capability is ideally suited to capturing rapidly evolving events. Theseexperiments will fall into one of two broadly applicable categories: single trigger anddual trigger experiments. Single trigger experiments involve a single impulse event thatevolves over time such as a laser-induced plasma or luminescence decay. Dual trigger
experiments involve two impulses separated in time such as double laser pulse
velocimetry measurements.

Requirements
The following requirements must be met for DIF operation:

the PI-MAX2 must use an interline CCD,
the controller must have a High Speed PCI Interface (TAXI) board and a PTG
board installed, andthe entire system must be set up for DIF operation at the factory.

In addition to these requirements, it is recommended that the intensifier have a fast decay
phosphor (P46 or P47). Since DIF operation involves acquiring images in rapid
succession, phosphor persistence can become the limiting factor in the rate of image
acquisition.
The WinX application software (version 2.5.16 or later) can control the DIF functionalityof the PI-MAX2 and provides full access to the two DIF timing modes: single trigger anddual trigger.

Interline CCD Operation
An interline CCD consists of alternating columns of light sensitive pixels and storage
pixels. The light sensitive columns are referred to as the active area and acquire theimage. The storage pixels are called the masked area and store the image in the dark
while it is read out. With this architecture, the CCD can acquire a second image while thefirst image is being read out, unlike a standard CCD, which must read out the first image
before the second acquisition can begin. The ability of the interline CCD to quickly
transfer an image under the masked columns and hold it there makes DIF possible. As
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second exposure begins and is held in the active area until the first image is read out.

Timing Modes
In the WinX application software, the timing modes available in the
Acquisition|Experiment Setup…|Timing tab are different from those in standard
intensified systems. The available timing modes are:Single Trig. Mode: two shot, one trigger for both shots.
Dual Trig. Mode: two shot, each shot requires a trigger.
The trigger(s) can be generated by an external source attached to the PTG or the PTG cangenerate the trigger(s) internally. When using a PTG internal trigger, the experiment will
normally be triggered by a signal from the ST-133. Typically, the rising edge of T0, fromthe PTG, is used.

Single Trigger Mode
The Single Trigger Mode only requires a single trigger to initiate the acquisition of both
images of the DIF operation. The Single Trigger Mode uses the Burst Mode feature of
the PTG to acquire two images from a single trigger event. On the Gating tab of thePulse dialog, the Burst Mode should be turned on. The Number of Pulses must be set to2, and the time between the images is set by the Burst Period. It is very important that the
Burst Period be large enough to accommodate the gate width, gate delay, and phosphor
decay time. To set the gate width and delay, select Repetitive Mode from the Gating tabof the Pulse dialog and then click on the Setup button.
Note: Sequential Mode will not create different gate width and delay for the two images
in Single Trigger Mode due to Burst Mode selection.

Figure 81. DIF Operation: Single Trigger Timing DiagramChapter 10

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Dual Trigger Mode
The Dual Trigger Mode requires two triggers to acquire both images of the DIF operation.
The PTG will control the gating of the intensifier for both images. To make the gate widthand delay the same for both images, select Repetitive Mode from the Gating tab of thePulser dialog then click the Setup button to set the values. To make the gate width anddelay different for each pulse, select Sequential Mode from the Gating tab of the Pulse
dialog, then click the Setup button to set the values. The Number of Images should be set to2, and the first image will use the starting values for gate width and delay while the second
image will use the ending values.

Figure 82. DIF Operation: Dual Trigger Timing Diagram

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Setup
HardwareFigure 83. System Diagram: DIF Operation

Software
For the purposes of this setup, it is assumed that you are using WinX application software(either WinView/32 or WinSpec/32) to control the system.

Operation
The operation of the PI-MAX2 in DIF mode is similar to the standard operation of a
PI-MAX2 with PTG. There are only a few differences due to the special timing modes of
DIF, and they will be outlined here. Because there are two timing modes in DIF
operation, there are two procedures for setting up the experiment.

Single Trigger Mode
1. The first requirement is that the PI-MAX2 camera be aligned and focused on thearea of interest in the experiment. This is best accomplished while the PI-MAX2
is operating in Interline mode (i.e., before switching to DIF mode). The
procedure for initial focus is outlined in Chapter 4: First Light.
2. After the alignment and focus, the PI-MAX2 system needs to be put into DIF
mode. Select Hardware from the Setup menu to open the Hardware dialog.
Under Readout Mode, select DIF and then click OK.
3. The PI-MAX2 must be set to Gate mode for the intensifier to operate properly.
Either click on the Gate mode button on the Custom Toolbar or select Gate
mode on the Acquisition|Experiment Setup…|Main tab.
4. Now the PTG needs to be programmed to match the experiment. On the Setup
menu, select Pulser and click on Pulser Setup (or click the Pulser Setup
button in the Custom Toolbar).

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a. In the Pulser dialog, select the Trigger tab. The PTG can be triggered by an
external trigger signal such as a TTL (typical settings for a TTL trigger mightbe: 1.7 V, positive edge, DC, 50 Ohm) or a photodiode (typical settings for a
photodiode might be: 8.0 V, positive edge, DC, high Z), or the PTG can use
its own internal clock to trigger the experiment. Select the appropriate one
for your experiment. In either case, the trigger frequency should be slow
enough so that the period between triggers is longer than the entire DIF
experiment. For example, if the Burst Period is 6 µs, then the trigger
frequency should be 8333 Hz [1 / (2 * 6 µs)].
b. Now select the Gating tab. In the Burst Mode section, turn Burst Mode on.
Set the Number of Pulses to 2. The Burst Period must be set to a value that isgreater than Gate Width + Gate Delay + Phosphor Decay. Ensure that the
Gating is set to Repetitive, and then click on the Setup button to set theappropriate gate width and delay.
c. At the bottom of the Pulser Setup dialog, click OK to download the gating
sequence to the PTG.
5. The CCD parameters need to be set to the appropriate values for DIF operation.
Select Experiment Setup from the Acquisition menu.
a. In the Timing tab, select Single Trig. Mode.
b. In the Main tab, verify that the Number of Images is 2 and the Intensifier isin Gate Mode.
c. When the experiment is ready, click the Acquire button to start the image
acquisition.

Dual Trigger Mode
1. As with Single Trigger Mode, the PI-MAX2 camera must first be aligned andfocused on the area of interest in the experiment. This is best accomplished while
the PI-MAX2 is operating in Interline mode (i.e., before switching to DIF mode).
The procedure for initial focus is outlined in Chapter 4: First Light.
2. The PI-MAX2 system needs to be put into DIF mode. In the Setup menu, open
the Hardware dialog. Under Readout Mode, select DIF and then click OK.
3. The PI-MAX2 must be set to Gate mode for the intensifier to operate properly.
Either click on the Gate mode button on the Custom Toolbar or select Gate
mode on the Acquisition|Experiment Setup…|Main tab.
4. Now the PTG needs to be programmed to match the experiment. In the Setup
menu, select Pulser and click on Pulser Setup (or click the Pulser Setup
button in the Custom Toolbar).
a. In the Pulser dialog, select the Trigger tab. The PTG can be triggered by an
external trigger signal such as a TTL (typical settings for a TTL trigger mightbe: 1.7 V, positive edge, DC, 50 Ohm) or a photodiode (typical settings for a
photodiode might be: 8.0 V, positive edge, DC, high Z), or the PTG can use
its own internal clock to trigger the experiment. Select the appropriate one
for your experiment. In either case, the trigger frequency should be slow
enough so that the period between triggers is longer than the Gate Delay +Gate Width + Phosphor Decay time.

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b. Now select the Gating tab. If the experiment can use the same gate widthand delay for both frames, then select Repetitive, and click on the Setup
button to set the appropriate gate width and delay. If the experiment requires
different gate widths or delays for each frame, then select Sequential andclick on the Setup button to set the appropriate gate widths and delays. The
number of images should be set to 2, the gate width and delay for the first
frame should be set as the starting values, and the width and delay for thesecond frame should be set as the ending values.
c. At the bottom of the Pulser Setup dialog, click OK to download the gating
sequence to the PTG.
5. The CCD parameters need to be set to the appropriate values for DIF operation.
Select Experiment Setup from the Acquisition menu.
a. On the Timing tab, select Dual Trig. Mode.
b. On the Main tab, verify that the Number of Images is 2 and the Intensifier
is in Gate Mode.
c. When the experiment is ready, click the Acquire button to start the image
acquisition.

Tips and Tricks
Experiments using the DIF feature of the PI-MAX2 can be complex, and timing of theevents is usually rather exacting. Here are several points to consider that may make theexperiment setup or troubleshooting much smoother and easier.


The most important piece of equipment in a DIF experiment is an oscilloscope.
The PI-MAX2 has a Gate Monitor signal on the back of the camera head which
is very useful for seeing when the two image exposures occur during the courseof the experiment. The use of the Gate Monitor and an oscilloscope is discussed
in more detail in Chapter 11: Tips and Tricks.

The short time between the two images in DIF requires an intensifier with a fast
phosphor. P46 phosphor as a decay time of ~ 2 µs, that means it takes 2 µs forthe phosphor emission to drop to 10% of its peak value. The decay is not a
simple single exponential; even after 100 µs there may be 1% or more of the firstimage on the phosphor screen. It is usually possible to subtract a percentage ofthe first image from the second image to remove the residual image. If this is notpossible, there are intensifiers with P47 phosphor, which is an order of magnitude
faster than P46.

The software uses the Shutter Compensation Time to determine how long to wait
after the gate pulse to shift the image. This value can be adjusted in the Hardware
Setup dialog. If there is some residual image from the first frame in the second
frame, simply increase the Shutter Compensation Time to allow the phosphor
more time to decay before shifting the image. If residual image is not an issue,
then Shutter Compensation Time can be shortened to decrease the time between
the two DIF images.

Chapter 11
Tips and Tricks
Introduction
In Chapters 4 and 7, the objective was to show how to take an image or spectrum with aminimal operating configuration and following a simple procedure. In this chapter, weconsider factors that affect more complex measurements.

Overexposure Protection
WARNING

Image intensified detectors such as the PI-MAX can be destroyed if exposed to excessive
light levels. Princeton Instruments cannot take responsibility for damage due to misuse.
Intensified detectors must not be continuously exposed to high-level radiation ( 10-4
foot candles). When the illumination level is not quantitatively known, toggle the MCP
On/Off switch (on the back of the PI-MAX) to the OFF position while you are adjusting
the incoming light level. After making adjustments, toggle the switch to the ON position.
If the alarm sounds continuously, toggle the switch back to OFF and readjust the lighting
conditions.
If the experimental conditions dictate that only a small portion of the photocathode isilluminated over relatively long periods of time, change the illuminated region of thephotocathode periodically to avoid long term localized photocathode or MCP damage.
Note: The audible alarm and protection circuits are not fail-safe protection, particularly
when working with high intensity sources such as lasers. For additional information, see
the "Alarm" discussion on page 82.

Signal Delay
Introduction
For the detector to see a transient signal, it is essential that it be gated on when the signal
arrives at the detector. If this requirement isn’t given careful consideration, it is possible
to set up an experiment in which the signal will come and go before the detector is gatedon. If this happens, no proper data can be taken. Depending on the nature of theexperiment and the specific equipment involved, a number of different factors may need
to be considered to be assured that the detector gates at the right time.

Time Budgets
A time budget is a listing of all the delays in the system that affect coincidence of thesignal and gate at the camera. Given a system that, in addition to the PI-MAX, ST-133,
and a pulse generator (PTG or DG535), contained a low-jitter pulsed laser triggered froman external timer and an external trigger source that is also triggering the pulse generator,
a time budget for this system might appear as follows.
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PTG
Signal Delay

Cable Delay from External Timer to Laser: 10 ns (6 ft cable is assumed)

Delay (at laser); Trigger to Laser Pulse: 50 ns

Delay; Laser Pulse to Sample: 10 ns
Delay; Fluorescence Signal to Detector: 45 ns
Total Signal Delay: 115 ns

Gate On Delay

Cable Delay from External Timer to PTG: 15 ns (10 ft cable is assumed)

PTG Insertion Delay; Trigger to Start of Gate Open Pulse: 25 ns

Cable Delay from PTG to Detector: 22 ns (15 ft cable is assumed)
Detector Insertion Delay: 15 ns
Total Gate On Delay: 77 ns

DG535
Signal Delay

Cable Delay from External Timer to Laser: 10 ns (6 ft cable is assumed)
Delay (at laser); Trigger to Laser Pulse: 50 ns
Delay; Laser Pulse to Sample: 10 ns
Delay; Fluorescence Signal to Detector: 45 ns
Total Signal Delay: 115 ns

Gate On Delay

Cable Delay from External Timer to DG535: 15 ns (10 ft cable is assumed)
DG535 Insertion Delay; Trigger to Start of Gate Open Pulse: 85 ns
Cable Delay from DG535 to Detector: 10 ns (6 ft cable is assumed)
Detector Insertion Delay: 15 ns
Total Gate On Delay: 125 ns
In this example, although the Signal Delay and the Gate On Delay are close, if the signal
is a pulse lasting only a few nanoseconds, it will have come and gone before the Gate
opens, and no valid experimental data could be taken. Obviously, this sample time budget
is unlikely to match any actual system and the values for both the Signal Delay and theGate On Delay could be very different from those indicated here. Nevertheless, itillustrates the importance of making a record of the delays that will be encountered in any
system to determine their possible impact on experimental results.

Measuring Coincidence
In addition to preparing a Time Budget, it is advantageous if you can directly measure thetiming of the critical signals. A fast oscilloscope can be used for this purpose. Without anoscilloscope to monitor the signals, it will be difficult to determine the timing with
sufficient accuracy.

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The PI-MAX Monitor BNC connector provides a pulse which, although delayed withrespect to the actual intensifier photocathode gating by 4-6 ns, quite accurately indicatesthe intensifier photocathode gating time. Note that this output is not designed for goodfidelity but rather for accurate timing. The amplitude is typically more than a volt and wesuggest that you monitor the pulse with a high impedance probe.
The signal timing will probably be more difficult to measure. Typically, you might divert
a small portion of the laser beam using a pellicle mirror located near the sample position.
By directing the beam to a PIN diode module, you could obtain an electrical signal that
could be monitored with the oscilloscope to accurately indicate the arrival of the laser
beam at the sample position. Note that the indicated time would have to be corrected forthe insertion delay of the path from the pellicle mirror to the oscilloscope, including theinsertion time of the PIN diode, which might be on the order of the 10 ns. This correction
would have to be compared with the delays that would normally exist between the sample
position and the detector to determine the actual time the signal would arrive at thedetector. Also, the oscilloscope will have its own insertion delay, perhaps 20 ns, and an
uncertainty of nominally 1% of the time base.
Another consideration is how to trigger the oscilloscope. If there is a common trigger
source for the sample position signal and for the gating, that trigger could also be used totrigger the oscilloscope, allowing both signals to be observed simultaneously. Anotherpossibility is to trigger the oscilloscope from the PIN diode signal to observe the Monitor
signal, or to trigger the oscilloscope from the Monitor signal to observe the PIN diodesignal. The signal that occurs first would have to be used as the oscilloscope trigger. This
is not necessarily always the case. Digital oscilloscopes can display signals that occur
before the trigger.
For even more precise measurement of the gate time, one can use the noise burst on the
Pulse Monitor output. The “noise” is actually induced voltage resulting from the fast risetime gate pulse and is within ~2 ns of the true optical gate.

Adjusting the Signal Delay
The PTG and DG535 give the user wide latitude with respect to adjusting the delay
between the time the timing generator is triggered and the time the Gate On and Offedges are generated. This being the case, as long as the light signal applied to the detector
occurs after the minimum delay time of the timing generator (25 ns for the PTG; 85 ns
for the DG535), there will be no problem establishing the necessary coincidence.
On the other hand, if the light signal applied to the detector occurs before the minimum
delay time of the timing generator, then no amount of adjusting the delay at the timing
generator can rectify the problem. The light signal itself will have to be delayed.
If a common source is triggering both the timing generator and the laser, a very
convenient solution is to insert electrical delay (long cable) between the trigger source
and the laser. This is generally preferable to establishing the necessary delay optically via
mirrors or fiber optic cable.
Alternatively, pass the laser output through a length of optical fiber cable. By using
different lengths of fiber, almost any desired signal delay can be achieved. Yet anothersolution would be to set up two separated parallel mirrors with a small angle between
them. Typically, it will be easily possible to bounce the laser beam back and forth
between the mirrors half a dozen times to obtain the necessary delay. In any case, once
the light signal is arriving at the detector after the minimum gate time, the timing
generator delay adjustments can be used to bring them into coincidence. Keep in mind

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that using optical cable or mirrors to delay the signal will carry some intensity penalty,
which might have an adverse affect on measurement results in some experiments.

Optimizing the Gate Width and Delay
When the basic delay questions have been answered, the next consideration is
optimization of the Gate Width and Delay. The goal is to have the gate just bracket thesignal event. One effective approach is to:
1. Begin with minimum delay and a gate width far wider than the optical signal pulse to
be measured.
2. While observing the data signal at the computer monitor, gradually increase the delay
until the event vanishes. This will mark the point at which the gate is opening justafter the signal, causing the signal to be lost.
3. Reduce the delay until the signal reappears.
4. Then begin reducing the gate width (not the delay). As the gate is narrowed, theamount of EBI generated will decrease so the signal-to-noise ratio should improve.
When the point is reached where the gate becomes narrower than the signal being
measured, the observed signal data will degrade. You may have to adjust the delay tokeep the signal in view.
5. From there increase the width slightly for maximum signal and optimum signal-tonoise.

LasersPulsed lasers are used in many experiments where a gated intensified detector might beused to recover the signal. For example, in combustion measurements, a laser pulse might
be applied to a flame and the resulting fluorescence studied as the signal to be analyzed.
Because this short-term signal is much weaker than the integrated light emitted by theflame, an intensified gated detector should be used to do the measurement.
Because available lasers differ so widely with respect to their characteristics and features,
there is no way to discuss specifically how to incorporate your particular laser into ameasurement system. It is necessary that users be familiar with the features, operation, andlimitations of their equipment. Nevertheless, the following observations might prove helpful.

Free Running Lasers
These lasers behave essentially as oscillators. They typically exhibit little jitter frompulse to pulse and are very easy to synchronize with the experiment. If the laser has a
Pretrigger Output, it can be used to trigger the timing generator. If the interval between
the Pretrigger and the laser output is long enough, the timing generator delay can then be
adjusted to catch the laser pulse following each pretrigger. If the interval between thePretrigger and the laser output isn’t long enough to accommodate all the insertion delays,
the timing generator delay can be adjusted to catch the next laser pulse. As long as thelaser’s jitter relative to the period is small, this is a perfectly valid way to operate. If thelaser doesn’t have a Pretrigger Output, one option is to use a pellicle mirror and a PIN
diode to obtain the timing generator trigger. Again, the timing generator delay could be
adjusted to catch the next laser pulse to achieve the necessary synchronization between
the optical signal and the photocathode gate at the detector, although this would cause atleast every other laser pulse to be lost.

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Triggered Lasers
Timing Generator as Trigger Source: Using the PTG’s T0 signal or the DG535’s
T0 output to trigger the laser allows you to get rid of the propagation delay for theExternal Trigger (25 ns for PTG and 85 ns for DG535) and to set up all timing relative to
T0. You will still need to consider the delays from the cable to the laser (1.5 ns/ft),
internal delay from trigger to firing (laser dependent, 50 ns for example), cabling fromthe ST-133 to the PI-MAX (1.5 ns/ft), the PI-MAX's internal delay (15 ns), and theminimum allowable gate delay (21 ns).
External Source Triggers Both Timing Generator and Laser: This is the more
complex case because it contains many sources of delay that would have to beconsidered. A carefully prepared Time Budget could prove invaluable in determining
what steps need to be taken to bring the gate and signal into coincidence at the detector.
In addition, actually measuring delays with a fast oscilloscope as previously described
could be very helpful. If the laser provides a Pretrigger output that can be used to trigger
the Timing Generator, it may not be necessary to use mirrors or fiber-optic cable to delay
the laser pulse. If there is no pretrigger, then taking steps to delay the arrival of the laser
pulse at the sample would likely be necessary. The easiest solution would be to insert
electrical delay between the external trigger source and the laser.

JitterJitter, uncertainty in the timing of the laser output, is a critical laser performanceparameter in gated experiments. If the jitter is significant relative to the duration of thesignal pulse, the gate width will have to be wide enough to accommodate it, and thetemporal discrimination against unwanted signal will be reduced. Some types of highpower laser pulse have considerable jitter, even using a pretrigger. Where this is the case,there is no choice but to trigger from the actual laser pulse. One way of doing that is touse a pellicle mirror and PIN diode as previously described and then to delay the light(usually by multiple reflections between mirrors or in an optical fiber) until the gate
“opens.”Inhibiting the Pulser during Readout
In Gate mode operation, if gating pulses are applied to the detector during a readout, it
will cause undesirable artifacts in the data. In experiments where the time between cycles
is longer than the readout time, there is no possibility of this happening and it is not amatter of concern. If the experiment is such that it is possible for a new gate to be applied
before the readout of the previously gathered data set is complete, preventive action will
be required. With a PTG, the timing generator is inhibited internally by the Controller.
With a DG535, it is necessary to connect a cable from the Shutter* output signal(provided at the ST-133’s
Output) to the Inhibit input of the DG535 (requiresthat the DG535 have the Inhibit Option installed).

Lens Performance
Imaging applications require that a lens be mounted to the detector. Because the lenscharacteristics affect system performance, it may be helpful to review some basic lensconcepts. Basically, light from an object enters the front of the lens and is focused to a

* NOT SCAN and SHUTTER are two different signals and must be set by jumper or software.

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sharp image on the photocathode of the intensifier. The ability of the lens to do this welldepends on a number of factors, as follows.

Throughput
The throughput of a lens is determined by its aperture, which can ordinarily be set to anumber of different values or f/ stops. The higher the number after the slash, the smaller
the aperture and the lower the throughput. Depth of field considerations make the focus
adjustment most sensitive at maximum aperture (smallest f/).

Resolution
This is a measure of the sharpness of the lens, that is, of its ability to resolve two closely
spaced lines. Resolution is commonly expressed as the Modulation Transfer Function(MTF), which specifies the number of line pairs per mm that can be resolved for a given
valley depth between the two lines of each pair. In comparing the MTF of two systems, it
is important that the specified valley depth for both be the same. For any real lens,
resolution is a function of f/#, with maximum sharpness most often occurring at some
mid-range value. Thus, a lens which offers f/# settings from f/ 2.8 to f/22 will probably
be sharpest at f/8 or f/11. For this reason, even though focusing may be more sensitive at
maximum aperture, actual data acquisition should be done with a mid-aperture setting.
When working with an intensified camera though, keep in mind that the resolution limit
will ordinarily be determined by the intensifier, not the lens, and light gathering power
becomes the principle concern for the lens.

Depth of Field
Depth of field is a measure of how the sharpness of a lens varies with respect to the
distance of an object from the lens. For any given aperture, there is a depth of field,
usually marked on the barrel of the lens. Objects within the zone will be sharply imaged.
Objects closer or further than the depth of field will not be as sharp. The further an object
is from the point of sharpest focus, the less sharp its image on the CCD will be. The pointof maximum sharpness is located 1/3 of the way into the depth of field zone. For example,
if the indicated depth of field for the selected aperture extended from 3 ft to 6 ft, the pointof maximum sharpness will be at 4 ft.
For good focusing sensitivity, the depth of field should be small (large aperture). If theaperture is small, the depth of field will be deep, making it difficult to establish the pointof sharpest focus. For example, with a 50 mm lens, at f/4 the depth of field will extend
from 8 ft to infinity. By focusing at full aperture, the depth of field will be as shallow as
possible. As a result, the effects of even very small focusing adjustments will be readily
observed, allowing the focus to be set with precision. Once the optimum focus setting has
been achieved, the aperture can be reduced to the point of maximum sharpness. In someexperiments, you may wish to adjust the aperture for optimum signal level. However, theexperiment setup parameters established with the applications software can also be used
to adjust the signal level, allowing the lens aperture and focus to be optimized.

Baseline Signal
With the detector completely blocked, the CCD will collect a dark charge pattern,
dependent on the exposure time, detector temperature, and intensifier gain setting. The
longer the exposure time and the warmer the detector the larger and less uniform thisbackground will appear.

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After temperature lock has been established, wait 30 minutes for the detector temperature
to completely stabilize. Then try taking a few dark charge readings with the detector
operated with the MCP On/Off switch set to OFF.
Note: Do not be concerned about either the baseline level of this background or its
shape, unless it is very high, i.e., > 1000 counts. What you see is not noise. It is a fully
subtractable readout pattern. Each CCD has its own dark charge pattern, unique to thatparticular device. Every device has been thoroughly tested to ensure its compliance with
Princeton Instruments' demanding specifications.

Temperature LockIf the PI-MAX Detector loses temperature lock, the internal temperature of the camera
has gotten too high, such as might occur if the operating environment is particularly
warm or if you are attempting to operate at a too cold temperature. If this happens, aninternal thermo-protection switch will disable the cooler circuits to protect them.
Although the thermo-protection switch will protect the camera, users are advised to
power down and correct the operating conditions that caused the thermal-overload tooccur. Note that the cooling performance of the detector can be enhanced by circulatingwater coolant. See "Temperature Control", page 57.
Turn the controller off for fifteen or twenty minutes. Then turn it back on and set a
warmer temperature from the software Detector Temperature dialog. Temperature lockshould be re-established within a few minutes.

Intensifier AlarmTo reduce the risk of detector damage, PI-MAX detectors are equipped with an audible
alarm in the detector head, activated when the intensity of light falling on the image
intensifier exceeds a preset threshold. While the alarm is sounding, the photocathode is
temporarily disabled. Toggle the MCP On/Off switch on the back of the PI-MAX to the
OFF position. Cover the detector window and only switch the MCP On/Off switch to
ON after the illumination level has been lowered. If the alarm sounds continuously evenwhen the illumination level is adequately low, shut the system down and contact thefactory for guidance.
Some controllers may also provide an audible alarm, indicating the same over-thresholdcondition as the detector alarm. Note that it is normal for the alarm to sound momentarily
when the system is turned on.

CautionContact the factory at once if sporadic or continuous unwarranted alarms occur. They
may indicate intensifier damage or another situation that requires immediate attention.

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Preamplifier Output Mode
PI-MAX detectors with the Thomson 512 × 512 chip have two auto-selected output
nodes. Node selection is done automatically from software depending on the A/D
converter speed. This allows performance to be optimized for a FAST converter (1 MHz)or for a SLOW one (500 kHz or slower but with superior noise performance). Thisfeature enhances the PI-MAX’s ability to provide outstanding performance in a wide
variety of applications.
Note that the node selection reverses the direction of data readout. When Slow is
selected, data readout begins with the longer (red) wavelength pixels and progresses tothe shorter (blue) wavelengths. When Fast is selected, the shorter wavelength pixels areread out first. In imaging, the effect is to reverse the image. These reversal effects areautomatically accommodated by the software and are transparent to the user. When theimage or spectrum is saved, the data will be in the order displayed at the computer.
Note: The order of the data at the ST-133’s Video Output connector will always
depend on the selected node. This reversal will be evident in the video monitor display
and cannot be accommodated. Again, as explained in the preceding paragraph, thedisplay at the computer is automatically corrected in software.

Chapter 12
Microscopy Applications
Introduction
This chapter discusses the setup and optimization of your digital imaging system asapplied to microscopy.
Since scientific grade cooled imaging systems are usually employed for low light level
microscopy, the major goal is to maximize the light throughput to the camera. In order todo this, the highest Numerical Aperture (NA) objectives of the desired magnification
should be used. In addition, you should carefully consider the transmission efficiency ofthe objective for the excitation and emission wavelengths of any fluorescent probes
employed. Another way to help maximize the transmission of light is to choose thecamera port that uses the fewest optical surfaces in the pathway, since each surface
results in a small loss in light throughput. Often the trinocular mount on the uprightmicroscope or the bottom port on the inverted microscope provide the highest lightthroughput. Check with the manufacturer of your microscope to determine the optimal
path for your experiment type.
A rule of thumb employed in live cell fluorescence microscopy is “if you can see thefluorescence by eye, then the illumination intensity is too high”. While this may not beuniversally applicable, it is a reasonable goal to aim for. In doing this, the properties ofyour camera should be considered in the design of your experiments.
Hardware binning can also be used to increase sensitivity. If sufficient detail will bepreserved, you can use 2 × 2 binning (or higher) to increase the light collected at each“super-pixel” by a factor of four or more. This will allow you to reduce exposure times,
thereby increasing temporal resolution and reducing photodamage to the living specimen.
Another way to minimize photodamage to biological preparations is to synchronize ashutter on the excitation pathway to the intensifier gate/shutter on the camera. This will
limit exposure of the sample to the potentially damaging effects of the excitation light.

Mounting the Camera on the Microscope
The camera is connected to the microscope via a standard type mount coupled to a
microscope-specific adapter piece. There are two basic camera mounting designs: theF-mount and the C-mount. The F-mount uses a tongue and groove type mechanism to alignthe camera with an adapter, while the C-mount employs a standard size thread to connect tothe adapter. Either or both types could be available for a specific camera model.

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F-Mount
For a camera with the F-mount type design, you will need two elements to mount thecamera on your microscope. The first element is a Diagnostic Instruments Relay Lens. Thislens is usually a 1× relay lens that performs no magnification. Alternatively, you may use a
0.6× relay lens to partially demagnify the image and to increase the field of view. There isalso a 2× relay lens available for additional magnification. The second element is a
microscope specific Diagnostic Instruments Bottom Clamp. Table 9 lists the bottom clamps
routinely used with each of the microscope types. They are illustrated in Figure 84. If you
think that you have received the wrong type of clamp, or if you need a clamp for a
microscope other than those listed, please contact Princeton Instruments.

Microscope Type

Diagnostic Instruments
Bottom Clamp Type

Leica DMR

L-clamp

Leitz All types

NLW-clamp®

Nikon Optiphot, Diaphot

O-clamp

Olympus BH-2, B-MAX, IMT-2

V-clamp

Zeiss Axioscope, Axioplan, Axiophot

Z-clamp

Zeiss Axiovert

ZN-clamp
Table 9. Bottom clamps for different type microscopes

To assemble the pieces, first pick up the camera and look for the black dot on the front
surface. Match this dot with the red dot on the side of the relay lens. Then engage the two
surfaces and rotate them until the F-mount is secured as evidenced by a soft clicking
sound. Now, place the long tube of the relay lens into the bottom clamp for yourmicroscope, securing the two together with the three setscrews at the top of the clamp as
shown in Figure 85. This whole assembly can now be placed on the microscope, using
the appropriate setscrews on the microscope to secure the bottom clamp to the output portof the microscope.
The F-mount is appropriate for any trinocular output port or any side port. Whenmounting the camera perpendicular to the microscope on the side port, we recommendthat you provide some additional support for your camera to reduce the possibility ofvibrations or excessive stress on the F-mount nose. Princeton Instruments does not advise
using an F-mount to secure the camera to a bottom port of an inverted microscope due topossible failure of the locking mechanism of the F-mount. Contact the factory for
information about a special adapter for operating in this configuration.

Chapter 12

Microscopy Applications

Figure 84. Diagnostic Instruments F-mount adapters

Figure 85. Bottom clamp secured to relay lens

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C-Mount
For a camera equipped with a C-mount thread, use a standard C-mount adapter suppliedby the microscope manufacturer to attach the camera to the microscope. If you don’t havean adapter, you can obtain one through your microscope distributor or you obtain dealer
information from Diagnostic Instruments at its website at www.diaginc.com.
The adapter can be screwed into the camera and then the assembly can be secured to themicroscope using the standard setscrews on the microscope. The camera can be mounted
on the trinocular output port, the side port or the bottom port of the inverted microscope.
When mounting the camera perpendicular to the microscope on the side port, werecommend that you provide some additional support for your camera to reduce thepossibility of vibrations or excessive stress on the C-mount nose. For the bottom port ofthe inverted microscope, the C-mount is designed to support the full weight of thecamera, however, you may wish to provide some additional support for the camera since
the detector is in a position where it could be deflected by the operator’s knee or foot.
This kind of lateral force could damage the alignment of the nose and result in suboptimal imaging conditions.
Most output ports of the microscope do not require additional optical elements to collectan image, however, please check with your microscope manual to determine if the chosen
output port requires any relay lens. In addition, all optical surfaces should be free fromdust and finger prints, since these will appear as blurry regions or spots and hence
degrade the image quality.

Operation
Xenon or Mercury Arc Lamp Precautions

WARNING Before You Start, if your system includes a microscope Xenon or Hg arc lamp, it is
CRITICAL to turn off all electronics adjacent to the arc lamp, especially your digital
camera system and your computer hardware (monitors also), before turning on the lamp
power.
Powering up your microscope Xenon or Hg lamp causes a large EMF spike to begenerated that can cause damage to electronics that are running in the vicinity of thelamp. We advise that you place a clear warning sign on the power button for your arc
lamp reminding all workers to follow this procedure. While Roper Scientific has taken
great care to isolate its sensitive circuitry from EMF sources, we cannot guarantee that
this protection will be sufficient for all EMF bursts.

Focusing the Microscope
1. Direct all of the light to the eyepieces
2. Focus on the target, set up Koehler illumination and adjust the condenser tomatch the objective, all in the transmitted light mode (as per the instructions
provided by your microscope manufacturer).
3. Decrease the transmitted light intensity to a level that is low, but still sufficient toallow visualization by eye.
4. Redirect the light to the camera port.

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Adjusting the Parfocality of the Camera
To adjust the parfocality on an F-mount system, begin collecting images with a short
exposure time and focus the light on the camera by rotating the ring on the Diagnostic
Instruments relay lens without touching the main focusing knobs on the microscope.
While adjusting parfocality, you will need to acquire images rapidly to minimize the delay
between the time a setting is changed and the time when the effect of the change can beobserved. The specifics of how to proceed will vary according to the application software.
In the WinX application software, select Acquisition, Video Focus. Begin with an
exposure time of 0.1 s. Then use Focus to begin data acquisition and Stop Acquisition to
end it when you are finished focusing. See your WinView/32 or WinSpec/32 manual for
additional information.
In IPLab, begin by selecting Set Camera from the Ext. menu. Set the dialog to
Asynchronous, 100 ms exposure, and 2 cleans. Establish Focus mode operation by
selecting Focusing from the Ext. menu. Set this dialog to 0.1 pixel seconds, 0-256 grayscale, and 1×. Press Start Camera to begin focusing and Stop Camera when finished. Seeyour IPLab manual for additional information.
Many PI cameras, both F-mount and C-mount, also make provision for extending the
focus range by providing a focus adjustment on the camera lens mount. If necessary, thisfocus can be changed to bring the image into range of the relay lens or other microscopefocus adjustment.

Imaging Hints
Determine the gray levels of the image by placing the cursor within the image andmonitoring the values shown. For optimal image quality of a 12-bit image, the highest
value in the field should be near 4000 counts but not at 4095 (which is saturating). You
may increase the number of counts by increasing your exposure, increasing the intensifier
gain, or by increasing the amount of light illuminating the specimen.
Note that adjusting the intensifier gain also affects the dark charge of the intensifier(EBI). To properly perform background subtraction a background must therefore bemeasured at each intensifier gain setting.

Fluorescence
Once you have acquired a suitable image in transmitted light mode, you may switch tofluorescence mode.
In fluorescence mode you generally want to minimize the bleaching of your sample,
usually achieved by placing several neutral density filters in the excitation pathway tominimize the illumination intensity. There will always be a trade-off here; when you
maximize signal quality by increasing the illumination intensity, you need to consider
whether your preparation can tolerate these conditions. In general, it is better to expose
longer with a lower intensity than to expose for a shorter time with a higher intensity;
nevertheless, your experimental conditions will dictate which path you take.
In fluorescence measurements you may not wish to maximize the gray levels in theimage, since this may cause bleaching of the dye or photodamage to the cell. Maintainthe minimum exposure required to get a sufficiently high quality image.

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If the scaling on the image does not appear good to the eye, you may use additional
scaling features available in the software. See your software manual for information on
how to properly use the contrast enhancing features of the program.

Microscopes and Infrared Light
Microscope optics have very high transmission efficiencies in the infrared region of thespectrum. Since the light sources are very good emitters in the infrared, somemicroscopes are equipped with IR blockers or heat filters to prevent heating of opticalelements or the sample.
For those microscopes that do not have the better IR blockers, the throughput of infrared
light to the camera can be fairly high. In addition, while the eye is unable to see the light,
some PI cameras are very efficient in detecting infrared wavelengths. As a result, thecontaminating infrared light will cause a degradation of the image quality due to a highbackground signal that will be invisible to the eye. Therefore, it is recommended that you
add an IR blocker prior to the camera if you encounter this problem with the microscope.

Chapter 13
TTL Control
Fully supported by WinSpec Version 2.5 when the communication protocol is
TAXI (PCI), this feature is not supported when the protocol is USB 2.0.

Introduction
Princeton Instrument's WinView/32 and WinSpec/32 software packages incorporate
WinX32 Automation, a programming language that can be used to automate performinga variety of data acquisition and data processing functions, including use of the TTL
In/Out functions. WinX32 Automation can be implemented in programs written in Visual
Basic. See the WinX32 documentation for more detailed information.
The TTL lines are made available through the TTL IN/OUT connector on the rear of the
ST-133 Controller. This connector provides 8 TTL lines in, 8 TTL lines out and an input
control line. Figure 86 illustrates the connector and Table 11 lists the signal/pin assignments.

TTL InThe user controls the 8 TTL Input lines, setting them high (+5 V; TTL 1) or low (0 V;
TTL 0). When the lines are read, the combination of highs and lows read defines adecimal number which the computer can use to make a decision and initiate actions as
specified in the user's program. If a TTL IN line is low, its numeric value is 0. If a TTL
IN line is high, its numeric value is as follows.
TTL INValue

TTL IN

Value

1

1

5

16

2

2

6

32

3

4

7

64

4

8

8

128

This coding allows any decimal value from 0 to 255 to be defined. Thus, as many as 256
different sets of conditions can be specified, at the user's discretion, using the TTL IN
lines. Any unused lines will default to TTL high (+5 V). For example, to define thenumber three, the user would simply set the lines TTL IN 1 and TTL IN 2 both high(+5 V). It would be necessary to apply TTL low to the remaining six lines because theywould otherwise default to TTL high as well.
TTL INValue

TTL INValue

1

High (1)5

Low (0)2

High (2)6Low (0)3

Low (0)7

Low (0)4

Low (0)8

Low (0)149

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Table 10 illustrates this coding for decimal values 0 through 7. Obviously this table could
easily be extended to show the coding for values all the way to 255.
DecimalEquiv.

TTLIN/OUT 8
1= dec 128

TTL
IN/OUT 7
1=dec 64TTL
IN/OUT 6
1=dec 32TTL
IN/OUT 5
1=dec 16TTL
IN/OUT 4
1=dec 8TTL
IN/OUT 3
1=dec 4TTL
IN/OUT 2
1=dec 2TTL
IN/OUT 1
1=dec 1

0

0

0

0

0

0

0

0

0

1

0

0

0

0

0

0

0

1

2

0

0

0

0

0

0

1

0

3

0

0

0

0

0

0

1

1

4

0

0

0

0

0

1

0

0

5

0

0

0

0

0

1

0

1

6

0

0

0

0

0

1

1

0

7

0

0

0

0

0

1

1

1

Table 10. Bit values with decimal equivalents:
1 = High,
0 = Low

Buffered vs. Latched Inputs
In controlling the TTL IN lines, users also have the choice of two input-line states,
buffered or latched. In the buffered state, the line levels must remain at the intended
levels until they are read. With reference to the preceding example, the high level at TTL
IN 1 and TTL IN 2 would have to be maintained until the lines are read. In the latchedstate, the applied levels continue to be available until read, even if they should change at
the TTL In/Out connector.
This control is accomplished using the EN/CLK TTL input (pin 6). If EN/CLK is open or
high, buffered operation is established and the levels reported to the macro will be thosein effect when the READ is made. With reference to our example, if pin 6 were left
unconnected or a TTL high applied, TTL IN 1 and TTL IN 2 would have to be held highuntil read. If, on the other hand, EN/CLK were made to go low while TTL IN 1 and TTL
IN 2 were high, those values would be latched for as long as EN/CLK remained low.
The levels actually present at TTL IN 1 and TTL IN 2 could then change withoutchanging the value that would be read by software.

TTL Out
The state of the TTL OUT lines is set from WinView/32 or WinSpec/32. Typically, a
program monitoring the experiment sets one or more of the TTL Outputs. Apparatus
external to the ST-133 interrogates the lines and, on detecting the specified logic levels,
takes the action appropriate to the detected condition. The coding is the same as for the
input lines. There are eight output lines, each of which can be set low (0) or high (1). The
combination of states defines a decimal number as previously described for the TTL IN
lines.

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TTL Control

151

Pin #

Assignment

Pin #Assignment

1

IN 1

14

IN 2

2

IN 3

15

IN 4

3

IN 5

16

IN 6

4

IN 7

17

IN 8

5

GND

18

GND

6

EN/CLK

19

Reserved

7(future use)

20

GND

8

GND

21

OUT 2

9

OUT 1

22

OUT 4

10

OUT 3

23

OUT 6

11

OUT 5

24

OUT 8

12

OUT 7

25

GND

13

Reserved
Table 11. TTL In/Out Connector Pinout

Figure 86. TTL In/Out
Connector

TTL Diagnostics Screen
Note that WinView/32 and WinSpec/32 provide a
TTL Diagnostics screen (located in under Hardware
Setup - Diagnostics) that can be used to test andanalyze the TTL In/Out lines.

Hardware Interface
A cable will be needed to connect the TTL In/Out
connector to the experiment. The design will vary
widely according to each user's needs, but astandard 25-pin female type D-subminiatureconnector will be needed to mate with the TTL
In/Out connector at the ST-133. The hardware at
Figure 87. TTL Diagnostics dialog
the other end of the cable will depend entirely on
the user's requirements. If the individual
connections are made using coaxial cable for maximum noise immunity (recommended),
the center conductor of the coax should connect to the proper signal pin and the cableshield should connect to the nearest available ground (grounds are conveniently provided
at pins 5, 8, 18 and 20). Connector hardware and cables of many different types arewidely available and can often be obtained locally, such as at a nearby electronics store.
A list of possibly useful items follows. Note that, although the items listed may beappropriate in many situations, they might not meet your specific needs.

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25-pin female type D-subminiature solder type connector (Radio Shack part no 2761548B).



RG/58U coaxial cable.



Shielded Metalized hood (Radio Shack part no 276-1536A).



BNC connector(s) type UG-88 Male BNC connector (Radio Shack part no 278-103).

ExampleSuppose you needed to build a cable to monitor the line TTL OUT 1. One approach
would be to build a cable assembly as described in the following paragraphs. This
procedure could easily be adapted to other situations.
1. Begin with a 25-pin female type D-subminiature solder type connector (Radio Shackpart no 276-1548B). This connector has 25 solder points open on the back.
2. Referring to Table 11 note that pin 8 = GND and pin 9 = TTL OUT 1.
3. Using coaxial cable type RG/58U (6 feet length), strip out the end and solder theouter sheath to pin 8 (GND) and the inner line to pin 9 (TTL OUT 1). Then apply
shielding to the lines to insulate them.
4. Mount the connector in a Shielded Metalized hood (Radio Shack part no276-1536A).
5. Build up the cable (you can use electrical tape) to where the strain relief clamp holds.
6. Connect a BNC connector (UG-88 Male BNC connector) to the free end of the cablefollowing the instructions supplied by Radio Shack on the box (Radio Shack part no278-103).
7. To use this cable, connect the DB25 to the TTL In/Out connector on the back of the
ST-133 controller.
8. To check the cable, start WinView/32 or WinSpec/32 and open the TTL Diagnostics
screen (located under Hardware Setup - Diagnostics). Click the Write radio button.
Then click the Output Line 1 box. Next click the OK button to actually set TTL
OUT 1 high. Once you set the voltage, it stays until you send a new command.
9. Measure the voltage at the BNC connector with a standard voltmeter (red on thecentral pin, black on the surrounding shielding). Before clicking OK at the TTL
Diagnostics screen you should read 0 V. After clicking OK you should read +5 V.
Note that adding a second length of coaxial cable and another BNC connector would bestraightforward. However, as you increase the number of lines to be monitored, it
becomes more convenient to consider using a multiple conductor shielded cable rather
than individual coaxial cables.

Chapter 14
System Component Descriptions
Introduction
PI-MAX is an advanced intensified CCD (ICCD) camera system used for low light andtime resolved applications. It consists of an imaging (square) or spectroscopy(rectangular) format CCD coupled to Generation II (PI-MAX RB, SB, UV) or Generation
III (PI-MAX HQ) intensifiers. The operation of the camera system is under complete
control of WinView/32 (Imaging) or WinSpec/32 (Imaging and Spectroscopy) software
packages. In pulsed/gated experiments, where the camera needs to be synchronized to alight source such as laser, an integrated Programmable Timing Generator™ (PTG) or an
external delay generator (e.g., DG535 from Stanford Research Systems) is used.

PI-MAX Camera
Mount Adapters
The nose at the front end of the PI-MAX camera is designed to accept three types ofmount adapters: C-mount, F-mount, and Spectroscopy-mount. The PI-MAX is suppliedwith the mount adapter specified when the system was ordered. For more information about
these mount adapters, refer to Appendix D for C- and F-mount adapters and refer toAppendix E for spectroscopy-mount adapters and spectrograph adapters.

Switches, Connectors and Indicators
Power/Signal connector: (standard
PI-MAX) 25-pin D connector; connects
to Controller cable (6050-0336); otherend of cable connects to Detector
connector of ST-133 Controller. See
Figure 88.
Signal connector: (PI-MAX2) 40-pin
connector; connects to Signal cable (60500492); other end of cable connects to
Signal connector of ST-133 Controller.
See Figure 89.
Power connector: (PI-MAX2) 15-pin D
connector; connects to Power cable(6050-0493); other end of cable connects
to Camera Pwr connector of ST-133
Controller. See Figure 89.

Figure 88. PI-MAX Rear Panel

Timing Gen connector: 9-pin D
connector; allows connections between
PI-MAX and the Timing Generator(PTG or Stanford Research DG535).
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Signals applied through this cable
control the photocathode gating and
MCP bracket pulsing.
MCP On/Off switch: This switch biases
the intensifier photocathode ON or OFF.
When the MCP On/Off switch is set to
ON, the photocathode can be gated ON.
Exception: Selecting SAFE on theExperiment Setup Main screen overrides
control and will prevent the photocathodefrom being biased on regardless of the
MCP On/Off switch setting.
When the MCP On/Off switch is set toOFF, then the photocathode cannot be
turned on from software.

CautionFigure 89. PI-MAX2 Rear Panel

It is advisable to set the MCP On/Off switch
to OFF as a fail-safe measure if the PI-MAX
is left ON but unused for a period of time.
Water ports: (standard PI-MAX) Two standard ¼ size brass fittings for circulatingwater coolant are located on the back panel. Either port may be used as the inlet. The
water cannot be chilled. A closed circulator such as the PI model CC-100 circulatingwater at laboratory ambient temperature should be used. See "Temperature
Control", page 57 for additional information.
Note: Although circulating water will extend the PI-MAX’s cooling capabilities, it is
not necessary. Most of the PI-MAX cooling is provided by the fan. With regard to theprocedures in this chapter, there is no need for circulating water coolant.
Monitor connector: BNC port for TTL logic 1 pulse delayed 4-6 ns with respect tophotocathode gating. Delay in 2 ns mode is not specified. Cable delay, ~1.5 ns/ft, will
be in addition to the delay at the connector.
Note: Operation of Monitor output with 6 ns gating cannot be guaranteed.
Excess Rep Rate: Red LED lights to warn of excessive repetition rate. Must be off for
proper operation.
Note: Excess Rep Rate LED is not activated by MCP bracket pulsing; MCP bracket
repetition rate limit is 5 kHz.
Trig: Green LED flashes each time PI-MAX is triggered. Glows steadily at highrepetition rates.

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Note: In gated operation, the green TRIG LED indicator flashes each time the
PI-MAX is triggered. In early units, however, the light may not flash with very shortgate times. The exact gate width at which this occurs varies from unit to unit but
typically this occurs at ~15 ns. This trigger detection aberration has no affectwhatsoever on the unit’s ability to make measurements with narrow gate widths. The
PI-MAX continues to gate normally and data acquisition continues to take place inthe usual manner.
Note that actual triggering can still be readily determined by either of two methods.
First, the Timing Generator, whether a PTG or a DG535, has its own Trigger LED
indicator. As long as triggering continues to be indicated at the Timing Generator, theuser can be reasonably confidant that the PI-MAX is triggering properly. Second, thesignal at the PI-MAX Monitor output can be observed with a fast oscilloscope.
Although the Monitor signal won’t be able to make the full logic level at the shortest
attainable gate times, its presence can be easily verified, indicating that proper
triggering is taking place.
Fan: Ventilation fan that runs continuously to remove heat generated by thethermoelectric cooler and the electronics. Air is drawn into the camera through theside ventilation slots, picks up the heat from the electronics and the cooler, and isthen exhausted through the back panel grill.
Thermoelectric Cooler: The thermoelectric (TE) cooler is mounted to the heat removal
block. With air-cooling alone, at an ambient temperature of 25C, temperature lock at 20 will generally occur within ten to twenty minutes. Note that the exact cooling
performance is a function of the CCD array installed. Also, if the lab is particularly
warm, achieving temperature lock might take longer or not occur at all.

ST-133 Controller
Electronics: The ST-133 controller is a compact, high performance CCD Camera
Controller for operation with Princeton Instruments brand* cameras. Designed for highspeed and high performance image acquisition, the ST-133 offers data transfer at speeds
up to 5 megapixel per second and standard video output for focusing and alignment. A
variety of A/D converters are available to meet different speed and resolution
requirements.
In addition to containing the power supply, the controller contains the analog and digitalelectronics, scan control and exposure timing hardware, and controller I/O connectors, allmounted on user-accessible plug-in modules. This highly modularized design gives
flexibility and allows for convenient servicing.

* The ST-133 controller must be factory configured for operation with an LN detector. For thisreason, a controller purchased for operation with an LN detector can only be used with an LN
detector. Similarly, a controller purchased for operation with a TE detector cannot be used withan LN detector.

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POWER Switch and Indicator: The powerswitch location and characteristics depend on theversion of ST-133 Controller that was shipped withyour system. In some versions, the power switch islocated on the on the front panel and has an integral
indicator LED that lights whenever the ST-133 ispowered. In other versions, the power switch islocated on the back of the ST-133 and does notinclude an indicator LED. Figure 90 shows the two
locations.
Rear Panel Connectors: There are three
Figure 90. Power Switch Location
controller board slots. Two are occupied by the(ST-133A and ST-133B)
plug-in cards that provide various controller
functions. The third, covered with a blank panel, is reserved for future development. The
left-most plug-in card is the Analog/Control module. Adjacent to it is the Interface
Control module. Both modules align with top and bottom tracks and mate with a passive
back-plane via a 64-pin DIN connector. For proper operation, the location of the modules
should not be changed. Each board is secured by two screws that also ground each
module’s front panel. The connectors and functions located on the rear panel are further aredescribed on the following page. Removing and inserting boards is described in Chapter 15,
pages 179-180.

WARNING! To minimize the risk of equipment damage, a module should never be removed or
installed when the system is powered.
The Analog/Control Module, which should always be located in the left-most slot,
provides the following functions.


Pixel A/D conversion

Timing and synchronization of readouts

CCD scan control



Temperature control

Exposure control

Video output control

The Interface Control Module, which should always be located in the center slot,
provides the following functions.


TTL in/out Programmable InterfaceCommunications Control (TAXI or USB 2.0 protocol)

WARNING! Always turn the power off at the Controller before connecting or disconnecting any cablethat interconnects the camera and controller or serious damage to the CCD may result.
This damage is NOT covered by the manufacturer’s warranty.

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Standard PI-MAX Controller Rear Panel Features: The descriptions of the rear panel connectors are
keyed to the accompanying figure. Depending on your system, either the TAXI or the USB 2.0 Interface
Control Module will be installed in the second from the left slot (as you face the rear of the ST-133). In the
Figure 91, the TAXI module is shown in that position. The Fuse/Voltage label will be above or below thePower Module.
#

Feature1

Temperature Lock LED: Indicates that thetemperature control loop has locked and thatthe temperature of the CCD array will be stable
to within  0.05C.

2

Video/Aux Output: If labeled Video,
composite video output is provided at thisconnector. The amplitude is 1 V pk-pk and thesource impedance is 75 . Note that video
output is not currently supported under USB
2.0. If labeled Aux, this output is reserved for
future use.

3

External Sync Input: TTL input that has a 10k pullup resistor. Allows data acquisition andreadout to be synchronized with external events.
Through software, positive or negative (default)
triggering can be selected.

4Output: WinView/32 (ver. 2.4 andhigher) software selectable NOT SCAN or
SHUTTER signal. Default is SHUTTER.

5

Output: Initially HIGH. Changes state
on completion of cleaning cycles before the first
exposure.

Figure 91. ST-133 (Standard) Rear Panel Callouts

6

Zero Adjustment: Bias potentiometers control
the offset values of the Fast (F) and Slow (S) A/D
converters. Preadjusted at factory. If
potentiometers are not present, bias may be
software-settable.

15

Timing Gen.: Gate Start/Stop and Bracket signals
are provided at this connector. This output must
be cabled to the PI-MAX Timing Gen connector.

7

Detector Connector: Transmits control
information to the camera and receives databack from the camera via the DetectorController cable.

16

Remote Shutter Connector: Unless the PI-MAX
system is powering a slit shutter for a spectrograph,this connector can be ignored.

8

TTL In/Out: User-programmable interface
with eight input bits and eight output bits thatcan be written to or polled for additional
control or functionality. Output is not currently
supported under USB 2.0. See Chapter 13.

17

Shutter Setting Selector: Sets the shutter holdvoltage. Unless the PI-MAX system is powering
a slit shutter for a spectrograph, this functionality
can be ignored.

9

AUX Output: Reserved for future use.

18

Aux. Trig. Out: AC-coupled variable delay trigger
output for synchronizing other system components
with PTG. The host software sets the Delay Time ofthis output with respect to the PTG trigger time.
This output does not need to be connected to the
PI-MAX.

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Feature#Feature10

Serial COM Connector: Provides two-way
serial communication between the controller andthe host computer.

19

Trig. LED: Trigger indicator. A 100 ms flash is
produced each time the PTG triggers. With
repetition rates faster than 10 Hz, indicator glows
continuously.

11Ext. Trig. In.: When external triggering isselected in the software, the PTG will be triggeredby an externally derived trigger pulse applied tothis input. The threshold (range ±5 V), slope,
coupling mode (AC or DC), and input impedance(High or 50 ) are selectable in software.

20

Power Module: Contains the power cord socket
and two fuses. Depending on the ST-133 version,
the power switch may be located directly above
the power module.

12Pre. Trig. In: TTL level used only to start a
bracket pulse.

21

Fuse/Voltage Label: Displays the controller’s
power and fuse requirements. This label may
appear below the power module.

13

T0 TTL Trigger output coincident with
PI-MAX gate. This output does not need to beconnected to the PI-MAX.

22

USB 2.0 Connector: Provides two-way serial
communication between the controller and the hostcomputer. Uses USB 2.0 protocol.

14

Fan: Cools the controller electronics. Runs
continuously when the controller is turned on.

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PI-MAX2 Controller Rear Panel Features: The descriptions of the rear panel connectors are keyed tothe accompanying figure. The TAXI Interface Control Module is installed in the second from the left slot (asyou face the rear of the ST-133). The Fuse/Voltage label will be above or below the Power Module.
#

Feature1

Temperature Lock LED: Indicates that thetemperature control loop has locked and thatthe temperature of the CCD array will bestable to within  0.05C.

2

Aux Output: This output is reserved for
future use.

3

External Sync Input: TTL input that has a
10 k pullup resistor. Allows data acquisition
and readout to be synchronized with external
events. Through software, positive or negative(default) triggering can be selected.

4Output: WinView/32 (ver. 2.4 andhigher) software selectable NOT SCAN or
SHUTTER signal. Default is SHUTTER.

5

Output: Initially HIGH. Changes state
on completion of cleaning cycles before the first
exposure.

Figure 92. ST-133 (PI-MAX2) Rear Panel Callouts
6

Camera Signal Connector: Transmits control
information to the camera and receives databack from the camera via the Signal cable(6050-0492).

14

Fan: Cools the controller electronics. Runs
continuously when the controller is turned on.

7

Camera Power Connector: Transmits power
to the camera from the Controller via thePower cable (6050-0493).

15

Timing Gen.: Gate Start/Stop and Bracket signals
are provided at this connector. This output must be
cabled to the PI-MAX2 Timing Gen connector.

8

TTL In/Out: User-programmable interface witheight input bits and eight output bits that can be
written to or polled for additional control orfunctionality. Output is not currently supported
under USB 2.0. See Chapter 13.

16

Remote Shutter Connector: Unless the PI-MAX2
system is powering a slit shutter for a spectrograph,this connector can be ignored.

9

AUX Output: Reserved for future use.

17

Shutter Setting Selector: Sets the shutter holdvoltage. Unless the PI-MAX2 system is powering
a slit shutter for a spectrograph, this functionality
can be ignored.

10

Serial COM Connector: Provides two-way
serial communication between the controller andthe host computer.

18

Aux. Trig. Out: AC-coupled variable delay trigger
output for synchronizing other system components
with PTG. The host software sets the Delay Time ofthis output with respect to the PTG trigger time. This
output does not need to be connected to the
PI-MAX2.

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Feature#Feature11

Ext. Trig. In.: When external triggering isselected in the software, the PTG will be triggeredby an externally derived trigger pulse applied tothis input. The threshold (range ±5 V), slope,
coupling mode (AC or DC), and input impedance(High or 50 ) are selectable in software.

19

Trig. LED: Trigger indicator. A 100 ms flash is
produced each time the PTG triggers. With
repetition rates faster than 10 Hz, indicator glows
continuously.

12Pre. Trig. In: TTL level used only to start a
bracket pulse.

20Power Module: Contains the power cord socket
and two fuses. Depending on the ST-133 version,
the power switch may be located directly above
the power module.

13

T0 TTL Trigger output coincident with
PI-MAX2 gate. This output does not need to beconnected to the PI-MAX2.

21

Fuse/Voltage Label: Displays the controller’s
power and fuse requirements. This label may
appear below the power module.

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Interface Card
PCI Card: This interface card is required when the system interface uses the TAXI
protocol rather than USB 2.0. The PCI card plugs-into the host computer'smotherboard and provides the serial communication interface between the hostcomputer and the ST-133. Through WinView/32 or WinSpec/32, the card can beused in either High Speed PCI or PCI(Timer) mode. High Speed PCI allows datatransfer to be interrupt-driven and can give higher performance in some situations.
PCI(Timer) allows data transfer to be controlled by a polling timer.
USB 2.0 Card: This interface card is required when the system interface uses theUSB 2.0 protocol rather the TAXI protocol and the computer does not have native
USB 2.0 support. The USB 2.0 card plugs-into the host computer's motherboard andprovides the communication interface between the host computer and the ST-133.
The USB 2.0 PCI card (70USB90011) by Orange Micro is recommended for desktop
computers; the SIIG, Inc. USB 2.0 PC Card, Model US2246 is recommended for
laptop computers. See www.orangemicro.com or www.siig.com , respectively, formore information.

Pulser
PTG: The optional Princeton Instruments Programmable Timing Generator (PTG)
is a plug-in module designed for operation in the ST-133. Incorporating the Timing
Generator into the Controller in this manner allows pulsed operation of the PI-MAX
Intensified Camera in pulsed measurements without the inconvenience and expenseof a separate timing generator.

DG535: The optional Stanford Research DG535 Digital Delay and Pulse Generator
can provide four precisely timed logic transitions or two precisely controlled pulses.
The four digitally controlled time intervals may be programmed from the front
panel or via the GPIB Interface. Front panel BNCs provide high slew rate outputs
for TTL, ECL, NIM or continuously adjustable levels. The outputs may be set todrive either 50 ohm or high impedance loads. The high accuracy (1 ppm), precision(5 ps), wide range (0 to 1000 s), and low jitter (50 ps) make the DG535 the ideal
solution to many difficult timing problems.
DG535s for use with a PI-MAX system should have Inhibit available at the front
panel. The Inhibit function is enabled in units purchased from Princeton
Instruments. All DG535s have the inhibit function; it's just not brought out to thefront panel in standard units. The modification to make Inhibit available at the front
panel is straightforward. A customer-owned DG535 can be easily modified by aqualified technician to implement the Inhibit Option. This can be done in the field
or at the factory. Contact Princeton Instruments for details. See page 232 for contact
information.

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The system may also include a spectrograph. If so, the camera must be properly mounted
to it as described in the manual supplied with the spectrograph. If the spectrograph will
be computer-controlled, a suitable interface cable will additionally be required. For
mounting instructions, see Appendix E, Spectroscopy-Mount and Spectrograph
Adapters, beginning on page 203.

Cables
The cables listed below may be supplied with the PI-MAX or PI-MAX2 system.
PI-MAX-Controller:
Standard PI-MAX: The standard 15' (4.6 m) cable (6050-0336) has DB-25
connector with slide-latch locking and screw-post hardware. This cableconnects the Power/Signal connector on the back of the PI-MAX to the
Detector connector on the back of the ST-133.
PI-MAX2: The standard 15' (4.6 m) cable set (6050-0499) has two cables.
One cable (6050-0492) interconnects the Signal and the Camera Signal
connectors on the PI-MAX2 and the ST-133, respectively. The other cable(6050-0493) interconnects the Power and the Camera Pwr connectors on the
PI-MAX2 and the ST-133, respectively.
Computer Interface Cable: Depending on the system configuration, either a USB
or a TAXI cable will be shipped.
TAXI: The standard 25' (7.6 m) cable (6050-0148-CE) has DB-9 Male
connectors with screw-down locking hardware. The TAXI (Serial
communication) cable interconnects the Serial Com connector on the rear of the
ST-133 with the PCI card installed in the host computer. In addition to thestandard length, this cable is available in 10', 50', 100', and 165' lengths. Also
available are fiber optic adapters with fiber optic cables in 100, 300, and 1000
meter lengths.
USB 2.0: The standard 16.4' (5 m) cable (6050-0494) has USB connectorsthat interconnect the USB 2.0 connector on the rear of the ST-133 with a
USB card installed in the host computer.

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PI-MAX to PTG: This 15' cable (6050-0406) is required if the system includes aPTG. This cable interconnects the Timing Gen connector on the PTG modulewith the Timing Gen connector on the PI-MAX.
PI-MAX to DG535: This 6' cable (6050-0385) is required if the system includes
a DG535. This cable assembly includes a Filter (2550-0347) for CE-compliance.
The cable connects via the Filter to the DB9 Timing Gen connector on the backof the PI-MAX, and to the A, B, and(or
depending on theintensifier type) BNC connectors of the DG535. The cable branches into three
BNC cables, one labeled A Start, one labeled B Stop, and the third C+D Gen
II/A+B Gen III.
Gen II Notes:
1. When this cable is left unconnected, the MCP will be biased
continuously ON. Normal photocathode gating will remain functional.
2. Leave this cable unconnected if the delay between trigger in and the gate
pulse is less than 1 µs.
For proper operation of a Gen III Intensified camera when gating, connect the
C+D-Gen II/A+B-Gen III cable to the DG535
BNC connector.
Gen III Note: Bracket pulsing is not allowed with Gen III Intensifiers. These
Intensifiers do not respond in the UV, negating any possible advantage tobracket pulsing.
DG535 to Computer: This 4 meter cable (6050-0170) is required if the system
includes a DG535. This is a standard IEEE 488 GPIB cable. It connects the IEEE488 GPIB Std Port connector on the back of the DG535 to the interface
connector of the computer's IEEE-488 GPIB Interface card. The DG535
parameter values are set by sending commands to the DG535 from the computer
via the application software (WinView/32 or WinSpec/32). Note that local
vendors may be able to supply the GPIB cable.
DG535 to Controller BNC cables:Cable connects BNC D output of the DG535 to the Controller's Ext. Sync
input. Tells the Controller to initiate an expose-readout cycle.

Cable connects the Controller's Shutter output signal (provided at ST-133's
Output) to the Inhibit input of the DG535 (must be equipped with
inhibit option). Inhibits the DG535 (and thus PI-MAX gating) during
readout.
Note that BNC cables may be available from local vendors. It is generally agood idea to have spare BNC cables on hand.

Other Cables
Other cables may also be required depending on the system requirements. For example,
there may be a BNC cable from the laser pre-trigger output or other master timing source
to the Trig In BNC connector of the DG535. Note also that the DG535 provides a T0
output that, although not required by the PI-MAX or Controller, could be used to trigger
or gate other system components. If the system includes a computer-controlled
spectrograph, an additional cable would be required to connect the spectrograph with thecomputer.

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Application Software
The Princeton Instruments WinView/32 or WinSpec/32 software package provides
comprehensive image acquisition, display, processing, and archiving functions so you
can perform complete data acquisition and analysis without having to rely upon thirdparty software. This software package provides reliable control over all Roper
Scientific cameras, regardless of array format and architecture, via an exclusive
universal programming interface (PVCAM®). Also featured are snap-ins and macro
record functions to permit easy user customization of any function or sequence.
PVCAM is the standard software interface for cooled CCD cameras from Roper
Scientific. It is a library of functions that can be used to control and acquire data fromthe camera when a custom application is being written. For example, in the case of
Windows, PVCAM is a dynamic link library (DLL). Also, it should be understoodthat PVCAM is solely for camera control and image acquisition, not for image
processing. PVCAM places acquired images into a buffer, where they can then be
manipulated using either custom written code or by extensions to other commerciallyavailable image processing packages.
Scientific Imaging ToolKit™ (SITK™) is a collection of LabVIEW® VIs forscientific cameras and spectrographs. This third party software can be purchasedfrom Princeton Instruments.

User Manuals
PI-MAX System User Manual: This manual describes how to install and use the
PI-MAX system components.
WinView/32 or WinSpec/32 User Manual: This manual describes how to installand use the application program. A PDF version of this manual is provided on the
installation CD. Additional information is available in the program's on-line help.

Chapter 15
Troubleshooting
CAUTION!

If you observe a sudden change in the baseline signal you may have excessive humidity
in the vacuum enclosure of the camera. Contact the factory for information on having thecamera vacuum repumped.

WARNING!

Do not attach or remove any cables while the camera system is powered on.

Introduction
The following issues have corresponding troubleshooting sections in this chapter.
Alarm Sounds Sporadically

Page 166

Alarm Sounds Continuously

Page 166

Baseline Signal Suddenly Changes

Page 166

Camera Stops Working

Page 166

Camera1 (or similar name) on Hardware Setup dialog

Page 167

Changing the ST-133 Line Voltage and Fuses

Page 168Controller Is Not Responding

Page 169

Data Loss or Serial Violation

Page 169

Data Overrun Due to Hardware Conflict message

Page 169

Data Overrun Has Occurred message

Page 170

Demo is only Choice on Hardware Wizard:Interface dialog(Versions 2.5.19.0 and earlier)

Page 170

Demo, High Speed PCI, and PCI(Timer) are Choices on Hardware
Wizard:Interface dialog (Versions 2.5.19.0 and earlier)

Page 172

Detector Temperature, Acquire, and Focus are Grayed Out(Versions 2.5.19.0 and earlier)

Page 174

Error Creating Controller message

Page 175

Error Occurs at Computer Powerup

Page 175

Excessive Readout NoisePage 177

No CCD Named in the Hardware Wizard:CCD dialog(Versions 2.5.19.0 and earlier)

Page 178

Program Error message

Page 178
165

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Removing/Installing a Plug-In Module

Page 179

Securing the Detector-Controller Cable Slide Latch

Page 181

Serial violations have occurred. Check interface cable.

Page 182

Temperature Lock Cannot be Achieved or Maintained

Page 182

Alarm Sounds Sporadically
It is normal for the alarm to sound briefly when the high-voltage supply is first turned on.
However, if the alarm sounds sporadically, contact the factory at once. This may indicate
intensifier damage or another situation that requires immediate attention.

Alarm Sounds Continuously
Immediately reduce the light entering the camera. This can be done by switching MCP
ON/OFF switch on the back of the PI-MAX to "OFF" until you lower the source
illumination, by decreasing the lens aperture, or by completely blocking the light into thecamera window with a lens cap or equivalent until the light level has be lowered.
If the alarm sounds continuously even when the illumination level is adequately low,switch the MCP ON/OFF to "OFF" and turn the ST-133 off. Then contact the factory: thismay indicate intensifier damage or another situation that requires immediate attention.

Baseline Signal Suddenly Changes
There are two possible reasons for this change: The temperature setting has been changed. In this case, a change in baseline signal isnormal.
 There may be excessive humidity in the intensifier enclosure of the camera. If thetemperature setting has not been changed and you observe a baseline signal change, turnoff the system immediately. An excess humidity condition should be corrected promptly
or permanent damage not covered by the Warranty could occur. Have the unit serviced
by Princeton Instruments or an authorized service facility of Princeton Instruments.

Camera Stops Working
Problems with the host computer system or software may have side effects that appear to
be hardware problems. If you are sure the problem is in the camera system hardware,
begin with these simple checks:







Turn off all AC power.
Verify that all cables are securely fastened and that all locking screws are in place
and all slide latches are in the latched position. For instructions on operating theslide latch locking mechanism, see "Securing the Detector-Controller Cable Slide
Latch", page 181.
Check for a burned-out fuse in the Controller power module. For information aboutchanging a fuse, see "Changing the ST-133 Line Voltage and Fuses" on page 168.
Correct any apparent problems and turn the system on.
If the system still does not respond, contact Customer Support.

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Camera1 (or similar name) on Hardware Setup dialog

Figure 93. Camera1 in Controller Type (Camera Name) Field

If you see a default name such as Camera1 on the Setup|Hardware|Controller/CCD
tab, you may want to change it since this name is not particularly descriptive. Such achange is made by editing the PVCAM.INI file that is generated by Camera Detection
wizard (or by the RSConfig.exe if you have software version 2.5.19.0 or earlier).
To change the default Camera Name:
1. Using Notepad or a similar text editor, open PVCAM.INI, which is located in
the Windows directory (C:\Windows, for example). You should see entries likethe ones below.
[Camera_1]
Type=1
Name=Camera1
Driver=apausb.sys
Port=0ID=523459
2. Change the "Name=" entry to something more meaningful for you (for example,
ST133USB - to indicate that this is a PVCAM-based system using an ST-133
with a USB 2.0 interface) and save the edited file.
[Camera_1]
Type=1
Name=ST133USB
Driver=apausb.sys
Port=0ID=523459
3. The new camera name will now appear in the Controller Type (Camera
Name) field.

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Changing the ST-133 Line Voltage and Fuses
The appropriate voltage setting for your country is set at the factory and can be seen on
the back of the power module. If your voltage source changes, you will need to change
the voltage setting and you may need to change the fuse configuration.

WARNING! Use proper fuse values and types for the controller and detector to be properly protected.
To Change Voltage and Fuse Configuration:

WARNING! Before opening the power module, turn the Controller OFF and unplug the power cord.
1. As shown in Figure 94, place the flat side ofa flat bladed screwdriver parallel to the backof the Controller and behind the small tab at
the top of the power module, and twist thescrewdriver slowly but firmly to pop themodule open.
2. To change the voltage setting, roll theselector drum until the setting that is closest
to the actual line voltage is facing outwards.
3. Confirm the fuse ratings by removing the two
white fuse holders. To do so, simply insert theflat blade of the screwdriver behind the front
tab of each fuse holder and gently pry theassembly out.

Figure 94. Power Input Module

4. Refer to the Fuse/Voltage label (above or
below the Power Module) to see which fuses
Figure 95. Fuse Holder
are required by the selected voltage. If theController power switch is on the back of the ST-133, the Fuse/Voltage label is locatedbelow the Power Module.
5. After inspecting and if necessary, changing the fuses to those required by the selectedvoltage, reinstall the holders with the arrow facing to the right.
6. Close the power module and verify that the correct voltage setting is displayed.
7. Verify that the Controller power switch is in the OFF position and then plug thepower cord back into the power module.

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Controller Is Not Responding
If this message pops up when you click on OK after selecting the Interface Type during
Hardware Setup (under the WinX Setup menu), the system has not been able tocommunicate with the camera. Check to see if the Controller has been turned ON and if
the interface card, its driver, and the interface cable have been installed.


If the Controller is ON, the problem may be with the interface card, its
driver, interrupt or address conflicts, or the cable connections.



If the interface card is not installed, close the application software and turn
the Controller OFF. Follow the interface card installation instructions in
Chapter 3 and cable the interface card to the "High Speed Serial" port on therear of the camera. Then do a "Custom" installation of WinSpec/32 or
WinView/32 with the appropriate interface component selected: "PCIInterface" or "ISA Interface", depending on the interface card type. Be sure
to deselect the interface component that does not apply to your system.



If the interface card is installed in the computer and is cabled to the "High
Speed Serial" port on the rear of the camera, close the application program
and turn the Controller OFF. Check the cable connections and secure theslide latches if the connections are loose.



If the interface card was installed after the WinX application software has
been installed, close the application program and do a "Custom" installationof WinSpec/32 or WinView/32 with the appropriate interface component
selected: "PCI Interface" or "ISA Interface", depending on the interface card
type. Be sure to deselect the interface component that does not apply to yoursystem.

Data Loss or Serial Violation
You may experience either or both of these conditions if the host computer has been set
up with Power Saving features enabled. This is particularly true for power saving withregard to the hard drive. Make sure that Power Saving features are disabled while you arerunning WinView/32 or WinSpec/32.

Data Overrun Due to Hardware Conflict message

Figure 96. Data Overrun Due to Hardware Conflict dialog

If this dialog appears when you try to acquire a test image, acquire data, or run in focus
mode, check the CCD array size and then check the DMA buffer size. A large array (forexample, a 2048x2048 array), requires a larger DMA buffer larger setting than that for asmaller array (for example, a 512x512 array).

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To change the DMA buffer setting:
1. Note the array size (on the Setup|Hardware|Controller/CCD tab or theAcquisition|Experiment Setup|Main tab Full Chip dimensions).
2. Open Setup|Environment|Environment dialog.
3. Increase the DMA buffer size to a minimum of 32 Mb (64 Mb if it is currently
32 Mb or 128 Mb if it is currently 64 Mb), click on OK, and close the WinX
application software.
4. Reboot your computer.
5. Restart the WinX application software and begin acquiring data or focusing. If
you see the message again, increase the DMA buffer size.

Data Overrun Has Occurred message
Because of memory constraints and the way that USB transfers data, a "Data overrun has
occurred" message may be displayed during data acquisition. If this message is displayed,take one or more of the following actions:
1. Minimize the number of programs running in the background while you are
acquiring data with the WinX application software (WinView/32 or WinSpec/32).
2. Run data acquisition in Safe Mode.
3. Add memory.
4. Use binning.
5. Increase the exposure time.
6. Defragment the hard disk.
7. Update the Orange Micro USB 2 driver. See "To Update the OrangeUSB USB
2.0 Driver:", page 40.
If the problem persists, your application may be USB 2.0 bus limited. Since the hostcomputer controls the USB 2.0 bus, there may be situations where the host computerinterrupts the USB 2.0 port. In most cases, the interrupt will go unnoticed by the user.
However, there are some instances when the data overrun cannot be overcome because
USB 2.0 bus limitations combined with long data acquisition times and/or large data sets
increase the possibility of an interrupt while data is being acquired. If your experimentrequirements include long data acquisition times and/or large data sets, your application may
not be suitable for the USB 2.0 interface. Therefore, we recommend replacement of the USB
2.0 interface module with our TAXI interface module and Princeton Instruments (RSPI) highspeed PCI card. If this is not the case and data overruns continue to occur, contact Customer
Support (see page 232 for contact information).

Demo is only Choice on Hardware Wizard:Interface dialog(Versions 2.5.19.0 and earlier)
If RSConfig.exe has not been run and there is not an installed Princeton Instruments (RSPI)
high speed PCI card, the Hardware Wizard will only present the choice "Demo" in theInterface dialog (Figure 97). Clicking on Next presents an "Error Creating Controller.
Error=129." message, clicking on OK presents "The Wizard Can Not Continue Without a
Valid Selection!" message, clicking on OK presents the Interface dialog again.

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Figure 97. Hardware Wizard: Interface dialog

At this point, you will need to exit the WinX application software (WinView/32 or
WinSpec/32) and run the RSConfig.exe program, which creates a file called
PVCAM.INI. This file contains information required to identify the interface/camera andis referenced by the Hardware Wizard when you are setting up the WinX application
software with USB for the first time:
1. If you have not already done so, close the WinX application software.
2. Make sure the ST-133 is connected to the host computer and that it is turned on.
3. Run RSConfig from the Windows|Start|Programs|PI Acton menu or from thedirectory where you installed the WinX application software.
4. When the RSConfig dialog (Figure 98) appears, you can change the camera nameto one that is more specific or you can keep the default name "Camera1". Whenyou have finished, click on the Done button.

Figure 98. RSConfig dialog

5. You should now be able to open the WinX application software and, from
Setup|Hardware…, run the Hardware Wizard.
6. When the PVCAM dialog (Figure 99) is displayed, click in the Yes radio button,
click on Next and continue through the Wizard. After the Wizard is finished, theController/Camera tab card will be displayed with the Use PVCAM checkbox
selected. You should now be able to set up experiments and acquire data.

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Figure 99. Hardware Wizard: PVCAM dialog

Demo, High Speed PCI, and PCI(Timer) are Choices on Hardware
Wizard:Interface dialog (Versions 2.5.19.0 and earlier)If there is an installed Princeton Instruments (RSPI) high speed card in the host computerand you want to operate a camera using the USB 2.0 interface, the PVCAM.INI file(created by RSConfig.exe) must exist and the USB 2.0 supported camera must be[Camera_1]. PVCAM.INI, which contains information required to identify theinterface/camera, is referenced by the Hardware Wizard when you are setting up the
WinX application software (WinView/32 or WinSpec/32) with USB for the first time. If
the Wizard did not find a PVCAM.INI file or if RSConfig.exe was run but the USB 2.0
camera is [Camera_2] in the PVCAM.INI file, "Demo", "High Speed PCI", and"PCI(Timer)" will be selectable from the Wizard's Interface dialog.

Figure 100. Hardware Wizard: Interface dialog

At this point, you will need to run the RSConfig.exe program:
1. If you have not already done so, close the WinX application software.
2. Make sure the ST-133 is connected to the host computer and that it is turned on.
3. Run RSConfig from the Windows|Start|Programs|PI Acton menu or from thedirectory where you installed the WinX application software.
4. When the RSConfig dialog (Figure 101) appears, you can change the camera
name to one that is more specific or you can keep the default name "Camera2".
When you have finished, click on the Done button. You will next edit thegenerated PVCAM.INI file.

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Figure 101. RSConfig dialog: Two Camera Styles

5. Using Notepad or a similar text editor, open PVCAM.INI, which is located in
the Windows directory (C:\Windows, for example).
If the contents of the file look like: Change the headings so the contents now look like:[Camera_1]
Type=1
Name=Camera1
Driver=rspipci.sys
Port=0[Camera_2]
Type=1
Name=Camera1
Driver=rspipci.sys
Port=0[Camera_2]
Type=1
Name=Camera2
Driver=apausb.sys
Port=0[Camera_1]
Type=1
Name=Camera2
Driver=apausb.sys
Port=0Note: The [Camera_#] must be changed so the camera supported by the USB
interface will be recognized (the USB driver is "apausb.sys"). For consistency,
you may also want to change the camera names.
6. Save the file. With the ST-133 connected and on, open the WinX application
software.
7. Run the Hardware Wizard.
8. When the PVCAM dialog (Figure 102) is displayed, click in the Yes radio
button, click on Next and continue through the Wizard. After the Wizard isfinished, the Controller/Camera tab card will be displayed with the Use
PVCAM checkbox selected. You should now be able to acquire data.

Figure 102. Hardware Wizard: PVCAM dialog

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Detector Temperature, Acquire, and Focus are Grayed Out(Versions 2.5.19.0 and earlier)
These functions and others will be deactivated if you have installed a camera being run
under USB 2.0 and have opened the WinX application software (WinView/32 or
WinSpec/32) without having first turned on the ST-133. They will also be deactivated if
you have installed a camera being run under USB 2.0 and a Princeton Instruments highspeed PCI card was also detected when RSConfig.exe was run.
1. Check to see if the ST-133 is connected to the host computer and is turned on. If
it is not connected or is connected but not turned on, go to Step 2. If it isconnected and on, go to Step 3.
2. Close the WinX application, verify that the ST-133 is connected to the hostcomputer, turn on the ST-133, and reopen the WinX application. The formerly
grayed out functions should now be available.
3. If the ST-133 is connected and on, the USB 2.0 camera may not be listed as
Camera 1 in the PVCAM.INI file.
4. Run RSConfig.exe (accessible from the Windows|Start|Programs|PI Actonmenu). If the USB 2.0 camera is listed as Camera 2 (Princeton Style (USB2) inFigure 103), you will have to edit the PVCAM.INI file.

Figure 103. RSConfig dialog: Two Camera Styles

5. Using Notepad or a similar text editor, open PVCAM.INI, which is located in
the Windows directory (C:\Windows, for example).
If the contents of the file look like: Change the headings so the contents now look like:[Camera_1]
Type=1
Name=Camera1
Driver=rspipci.sys
Port=0[Camera_2]
Type=1
Name=Camera1
Driver=rspipci.sys
Port=0[Camera_2]
Type=1
Name=Camera2
Driver=apausb.sys
Port=0[Camera_1]
Type=1
Name=Camera2
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Note: The [Camera_#] must be changed so the camera supported by the USB
interface will be recognized (the USB driver is "apausb.sys"). For consistency,
you may also want to change the camera names.
6. Save the file. With the ST-133 connected and on, open the WinX application
software. The formerly grayed out functions should now be available.

Error Creating Controller message
This message may be displayed if you are using the USB 2.0 interface and have not run
the RSConfig.exe program (see previous topic), if the PVCAM.INI file has beencorrupted, or if the ST-133 was not turned on before you started the WinX application
software (WinView/32 or WinSpec/32) and began running the Hardware Wizard.

Figure 104. Error Creating Controller dialog

Error 129: Indicates that the problem is with the PVCAM.INI file. Close the WinX
application software (WinView/32 or WinSpec/32), run RSConfig, make sure theST-133 is on, reopen the WinX application software, and begin running the
Hardware Wizard.
Error 183: Indicates that the ST-133 is off. If you are running the Hardware Wizard
when this message appears, click on OK, turn on the ST-133, and, on the PVCAM
dialog, make sure Yes is selected and then click on Next. The Hardware Wizard
should continue to the Controller Type dialog.

Error Occurs at Computer Powerup
If an error occurs at boot up, either the Interface is not installed properly or there is anaddress or interrupt conflict. Turn off the computer, try a new address or interrupt andreinstall the card. Be sure the Interface is firmly mounted in the slot.

Caution

Since interrupts and DMA channels cannot be shared, make sure no other boards in yourcomputer use this interrupt or these DMA channels.

Conflicts
One of the many advantages that PCI offers over ISA is that the whole issue of address
and interrupt assignments is user transparent and under BIOS control. As a result, users
typically do not have to be concerned about jumpers or switches when installing a PCI
card. Nothing more should be required than to plug in the card, make the connections,and operate the system. As it turns out, however, in certain situations conflicts may
nevertheless occur and user intervention will be required to resolve them.
Typical PCI motherboards have both ISA and PCI slots and will have both PCI and ISA
cards installed. In the case of the ISA cards, the I/O address and Interrupt assignments
will have been made by the user and the BIOS will not know which addresses andinterrupts have been user assigned. When a PCI card is installed, the BIOS checks for

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available addresses and interrupt levels and automatically assigns them so that there are
no PCI address or interrupt conflicts. However, because the BIOS doesn't know about theuser-assigned ISA I/O address and interrupt level assignments, it is possible that a PCI
card will be assigned an address or interrupt that is already assigned to an ISA card. If
this happens, improper operation will result. Specifically, the problems could range fromerratic operation under specific conditions to complete system failure. If such a conflictoccurs, because the user has no control over the PCI address and interrupt assignments,
there will be no recourse but to examine the ISA assignments and change them to values
that do not conflict. Most (but by no means all) ISA cards make provision for selecting
alternative I/O addresses and interrupt levels so that conflicts can be resolved. Software isavailable to help identify specific conflicts.
The following example may serve to illustrate the problem. Suppose you had a system withan ISA network card, a PCI video card and an ISA sound card. Further suppose that you werethen going to install a PCI Serial Buffer card. Before installing the PCI Serial card, the I/O
address and interrupt assignments for the installed cards might be as indicated in Table 12.
Slot Type

StatusI/O Address

Interrupt

1 (ISA)ISA Network Card200-21011

2 (PCI)PCI Video Card

FF00-FFFF

15

3 (ISA)ISA Sound Card

300-3049

4 (PCI)

Empty

N/A

N/A

Table 12. I/O Address & Interrupt Assignments
before Installing Serial Card

As shown, there are no conflicts, allowing the three peripheral cards to operate properly.
If the PCI Serial card were then installed, the BIOS would interrogate the PCI cards andmay reassign them new address and interrupt values as follows.
Slot Type

StatusI/O Address(s)Interrupt

1 (ISA)ISA Network Card200-21011

2 (PCI)PCI Video Card

FE00-FEFF

11

3 (ISA)ISA Sound Card

300-3049

4 (PCI)

Princeton Instruments(RSPI) PCI Serial Card

FF80-FFFF

15

Table 13. I/O Address & Interrupt Assignments
after Installing Serial Card

As indicated, there is now an interrupt conflict between the ISA Network Card and the
PCI Video card (both cards have been assigned Interrupt 11), causing the computer to nolonger function normally. This doesn't mean that the PCI Serial card is defective because
the computer stops functioning properly when the Serial card is installed. What it doesmean is that there is an interrupt conflict that can be resolved by changing the interrupt
level on the conflicting Network card in this example. It is up to the user to consult the
documentation for any ISA cards to determine how to make the necessary change.

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Note: Changing the order of the PCI cards, that is, plugging them into different slots,
could change the address and interrupt assignments and possibly resolve the conflict.
However, this would be a trial and error process with no guarantee of success.

Diagnostics Software
Many diagnostics programs, both shareware and commercial, are available to help
resolve conflicts. Most often, all that's required is a program that will read and report theaddress and interrupt assignments for each PCI device in the computer. One suchprogram available from Princeton Instruments' Customer Support department is called
PCICHECK. When the program is run, it reports the address and interrupt assignments
for the first PCI device it finds. Each time the spacebar is pressed, it moves on to the next
one and reports the address and interrupt assignments for that one as well. In a few
moments this information can be obtained for every PCI device in the computer. Note
that, even though there are generally only three PCI slots, the number of PCI devices
reported may be larger because some PCI devices may be built onto the motherboard. A
good strategy for using the program would be to run it before installing the PCI Serialcard. Then run it again after installing the card and note any address or interrupt
assignments that may have changed. This will allow you to easily focus on the ones that
may be in conflict with address or interrupt assignments on ISA cards. It might be notedthat there are many programs, such as the MSD program supplied by Microsoft, that aredesigned to read and report address and interrupt assignments, including those on ISA
cards. Many users have had mixed results at best using these programs.

Operation
There are no operating considerations that are unique to the PCI Serial card. The card caneasily accept data as fast as any Princeton Instruments system now available can send it.
The incoming data is temporarily stored in the card's memory, and then transferred to themain computer memory when the card gains access to the bus. The PCI bus arbitration
scheme assures that, as long as every PCI card conforms to the PCI guidelines, the onboard memory will never overflow.
Unfortunately, there are some PCI peripheral cards that do not fully conform to the PCI
guidelines and that take control of the bus for longer periods than the PCI specification
allows. Certain video cards (particularly those that use the S3 video chip) are notorious inthis respect. Usually you will be able to recognize when memory overflow occurs
because the displayed video will assume a split-screen appearance and/or the message
Hardware Conflict will be displayed (WinView/32). At the same time, the LED on theupper edge of the PCI Serial card will light.
Users are thus advised not to take any actions that would worsen the possibility ofmemory overflow occurring when taking data. In that regard, avoid multitasking while
taking data. Specific operations to avoid include multitasking (pressing ALT TAB or
ALT ESC to start another program), or running a screensaver program.

Excessive Readout Noise
Excessive readout noise with the intensifier off indicates possible moisture accumulationin the CCD. This should be corrected promptly or permanent damage not covered by the
Warranty could occur.
Normal camera noise is a function of the gain setting and temperature as well as CCD
type, but is typically in the range of 1 ADU rms (6 ADU pk-pk). This is on top of offset
that typically is about 40 counts. Moisture accumulation produces a coarser noise with

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many spikes  30 ADU. If these types of spikes occur, especially after the camera has
been in use for an extended period, turn off the system immediately. Have the unit
serviced by Princeton Instruments or an authorized service facility of Princeton
Instruments.

No CCD Named in the Hardware Wizard:CCD dialog(Versions 2.5.19.0 and earlier)Figure 105. Hardware Wizard: Detector/Camera/CCD dialog

If you have installed a USB 2.0 Interface Module in your ST-133, a blank field may bedisplayed in the Detector/Camera/CCD dialog (Figure 105) if the ST-133 controller was
made before January 2001. Earlier versions of the ST-133 did not contain non-volatile
RAM (NVRAM), which is programmed with information about the controller and thecamera. PVCAM, the program under which the Princeton Instruments USB works,
retrieves the information stored in NVRAM so it can enter specific camera characteristics
into the WinX application software..
Check the serial label on underside of your controller. If the first five characters are
D1200 (December 2000) or earlier (J0797 or July 1997, for example), contact Customer
Support to find out about an NVRAM controller upgrade.

Program Error message

Figure 106. Program Error dialog

This dialog may appear if you have tried to acquire a test image, acquire data, or run infocusing mode and the DMA buffer size is too small. A large array (for example, a2048x2048 array), requires a larger setting than that for a smaller array (for example, a
512x512 array).
To correct the problem:
1. Click on OK.
2. Reboot the WinX application software (WinView/32 or WinSpec/32).
3. Note the array size (on the Setup|Hardware|Controller/CCD tab or theAcquisition|Experiment Setup|Main tab Full Chip dimensions). If your

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camera contains a large array (such as a 2048x2048 array), and the DMA buffer
size is too small, there will not be enough space in memory for the data set.
4. Open Setup|Environment|Environment dialog.
5. Increase the DMA buffer size to a minimum of 32 Mb (64 Mb if it is currently 32
Mb or 128 Mb if it is currently 64 Mb), click on OK, and close the WinX
application software.
6. Reboot your computer.
7. Restart the WinX application software and begin acquiring data or focusing. If
you see the message again, increase the DMA buffer size.

Removing/Installing a Plug-In Module
The ST-133 Controller has three plug-in slots. The Analog/Control module (leftmost slot
when the controller is viewed from the rear) and the Interface Control module (either a
TAXI or a USB 2.0 compatible module in the middle slot) are always provided. The thirdslot, however, is covered with a blank panel unless a PTG module has been installed in
the ST-133.
If a module is ever removed for any reason, internal settings should not be disturbed.
Changing a setting could radically alter the controller’s performance. Restoring normal
operation again without proper equipment and guidance would be very difficult, and it
might be necessary to return the unit to the factory for recalibration.
Note: If you have an installed PTG and are changing from one interface type to another(TAXI to USB 2.0 or USB 2.0 to TAXI), contact Customer Support for specificchangeover instructions. See page 232 for contact information.

WARNINGS!

1. Always turn the Controller OFF before removing or installing a module. If a
module is removed or installed when the controller is powered, permanentequipment damage could occur which would not be covered by the warranty.
2. Before handling any boards, take precautions to prevent electrostatic discharge(ESD). The modules are susceptible to ESD damage. Damage caused by
improper handling is not covered by the Warranty.

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Figure 107. Module Installation

To Remove a Module:
1. Verify that the Controller has been turned OFF.
2. Rotate the two locking screws (one at the top of the module and one at the bottom)
counterclockwise until they release from the chassis.
3. Then, grasp the module and pull it straight out.
4. Set the module aside in a safe place. If you are replacing it with another module, as in thecase of exchanging a TAXI module for a USB 2.0 module, you may be able to use thepackaging from the new module to store the old module. This packaging is usually anantistatic bag that will protect the module components from electrostatic discharge.
To Install a Module:
Installing a module is a bit more complex because you first have to be sure the locking
screws are aligned correctly. The following procedure is suggested.
1. Verify that the Controller has been turned OFF.
2. Remove the replacement module from its antistatic packaging. This packaging isdesigned to protect the module components from electrostatic discharge.
3. Rotate the two locking screws counterclockwise until the threads on the screws engage
those of the module panel. See Figure 107. By doing this, the screws will be perfectly
perpendicular to the module panel and will align perfectly when the module is inserted.
4. Insert the module so the top and bottom edges of the board are riding in the proper
guides.
5. Gently but firmly push the module in until the 64-pin DIN connector at the back of themodule mates with the corresponding connector on the backplane, leaving the module
panel resting against the controller back panel.
6. Rotate the two locking screws clockwise. As the screws are rotated, they will firstdisengage from the module panel threads, and then begin to engage those of the bracket
behind the controller panel.

WARNING!

Tighten the screws to where they are just snug. Do not tighten them any further because
you could easily bend the mating bracket.

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Securing the Detector-Controller Cable Slide Latch
Some Princeton Instruments Detector-Controller cables use a slide latch to secure theDetector-Controller cable to the DETECTOR connector on the back of the ST-133.
Incorrectly plugging this cable into the connector and improperly securing the slide latch
may prevent communication with the PI-MAX (the camera may appear to stop working).
1. Before trying to plug in the cable, slide the latch up (toward Pin 1). Then, plug thecable into the DETECTOR connector on the ST-133.

2. Slide the latch down. You may hear a click when the latch locks.

3. Verify that the connector is fully secured.
If you are having trouble sliding the latch, slightly pull the connector out and then slide
the latch into its locked position.

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Serial violations have occurred. Check interface cable.

Figure 108. Serial Violations Have Occurred dialog

This error message dialog will appear if you try to acquire an image or focus the cameraand either (or both) of the following conditions exists:The camera system is not turned ON.

There is no communication between the camera and the host computer.

To correct the problem:
1. Turn OFF the camera system (if it is not already OFF).
2. Make sure the Detector-Controller cable is secured at both ends and that thecomputer interface cable is secured at both ends.
3. After making sure that the cables are connected, turn the camera system powerON.
4. Click OK on the error message dialog and retry acquiring an image or running infocus mode.
Note: This error message will also be displayed if you turn the camera system OFF or acable comes loose while the application software is running in Focus mode.

Temperature Lock Cannot be Achieved or Maintained
Possible causes could include: High ambient temperature.
 Airflow through the camera is blocked.
 The camera fan is not running.
 Coolant flow rate is too slow.
 The connectors on the Detector-Controller cable need to be secured.
 The target array temperature is not appropriate for your particular camera and CCD array.
 You are trying to operate at a temperature colder than the specified limit. TE-cooled
cameras have a thermal-protection switch that shuts off the cooler circuits if the internal
temperature exceeds a preset limit. Typically, camera operation is restored automaticallyin about ten minutes. Although the thermo-protection switch will protect the camera, it isadvisable to power down and correct the operating conditions that caused the thermaloverload.

Appendix A
Specifications
ATTENTION

The following specifications are subject to change. Contact the factory or go towww.princetoninstruments.com for the latest information on performance, options, andaccessories.

GeneralCCD Array

Well Capacity

Read Noise

Sensitivity

Marconi (EEV) CCD30-11 500 ke- for single
8 e- rms @ 100 kHz; 151024 × 256: full frame,
pixel; 1.2 Me with e- rms @ 1 MHz
26 × 26 µm pixels
binning

Software selectable; 1 to
80 ADU/photoelectronThomson 7895
512 × 512: 19 × 19 µm
pixels (effective size 24 ×
24)

450 ke- for single<8 e- rms @ 100 kHz;pixel; 1.2 Me with <35 e- rms @ 1 MHz;binning<50 e- rms @ 5 MHz

Software selectable; 1 to
80 ADU/photoelectron(standard PI-MAX), 4 to
300 ADU/photoelectron(PI-MAX2)

Marconi CCD47-10 1024
× 1024: 13 × 13 µm pixels

100 ke- for single
pixel<8 e- rms@ <100 kHz;11 e- rms @ 1 MHz

Software selectable; 6 to
80 ADU/photoelectron

Kodak 1003M 1024 ×
1024: interline, 12.8 ×
12.8 µm pixels

130 ke- for single
pixel<11 e- rms @ 1 MHz;<16 e- rms @ 5 MHz

Software selectable; 4 to
300 ADU/photoelectron

Digital Conversion: 16 bits
Image Intensifier: 18 mm or 25 mm
Method of Coupling: 1:1 fiber optics for most models (1.27:1 for Thomson 512)
Mounts: Three different interchangeable mounts/adapters are available so that C-mountlenses, F-mount lenses, and spectrograph can all be readily accommodated.
Changeover from one mounting system to another can be accomplished in momentswith no adjustments required. Any one of the three mount types simply screws into
the PI-MAX nose until it bottoms out. It is then secured by the three locking
setscrews, which require a 0.050 hex key. Available mounts include:
Spectroscopy Adapter: three 120° slots in concentric configuration with 3.6" bolt
circles.
F-Mount Adapter:* accepts standard F-mount latching mechanism.

* Similar mount for Canon lenses may also be available. Contact factory for information.

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C-Mount (microscopy) Adapter: accepts standard C-mount threaded lenses.
Note: C-mount detectors are shipped with a dust cover lens installed. Although thislens is capable of providing surprisingly good images, its throughput is low and theimage quality is not as good as can be obtained with a high-quality camera lens.
Users should replace the dust-cover lens with their own high-quality laboratory lensbefore making “real” measurements.
Focal Depth (distance from adapter flat to photocathode surface)
Spectroscopy: 0.894"
F-Mount: 46.5 mm
C-Mount: 17.5 mm (0.690")
Vignetting: With fiber optic coupling there is no vignetting. With a 1024 × 256 array,
which has a width of 26 mm, pixels that fall beyond the 18 mm or 25 mm width(depending on intensifier width) of the intensifier will not be illuminated.
Gen II Spatial Resolution
1:1 coupling: typically 70 µm spot size FWHM
1.27:1 coupling: typically 55 µm spot size FWHM
Gen II High Res Spatial Resolution
1:1 coupling: typically 45 µm spot size FWHM
1.27:1 coupling: typically 40 µm spot size FWHM
Gen III Spatial Resolution
1:1 coupling: typically 42 µm spot size FWHM
1.27:1 coupling: typically 38 µm spot size FWHM
Geometric Distortion: typically < 1 pixel
Sensitivity: Variable intensifier gain adjustment (via software) allows sensitivities from1-80 counts per photoelectron. Some phosphor choices may result in lower
values.
Gating ON/OFF Ratio
Visible (550 nm): 5 x 106:1 typicalUV (250 nm): 104:1 with photocathode gating only; 106:1 with supplemental
MCP bracket pulsing typical.
Response Linearity: Better than 1% for the upper 95% of range in ungated operation.
Slightly non-linear response at lower 5% of range, due to phosphor nonlinearity.
Photocathode Dark Charge (EBI): Red-blue enhanced, < 5 counts/pixel-second;
Red-enhanced, < 15 counts/pixel-second
Phosphor Decay: 2 ms P43 standard, 1 µs P46 phosphor is optional
Spectral Range
Gen II: Red-blue enhanced, 180-900 nm; Red enhanced, 360-920 nm
Gen III: HQ, 450-900 nm (3 dB cutoff wavelengths); HQ (Blue), 375-900 nm
Nonuniformity: Typically 12% pk-pk for Gen II 18 mm intensifiers, 16% pk-pk for
Gen II 25 mm intensifiersAppendix A

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185

CCD Cooling: down to -20°C air cooled; supplementary cooling with circulating roomtemperature water will enhance cooling performance. Temperatures to -45°C areachievable with supplemental circulating chilled coolant.
Note: See warning in "Temperature Control", page 57 before initiating
supplemental water cooling.
Readout Noise: 1-1.5 counts RMS in gated operation (100 kHz).

Computer
Requirements for the host computer depend on the type of interface, TAXI or USB 2.0,
that will be used for communication between the ST-133 and the host computer. Thoserequirements are a listed below according to protocol.
TAXI Protocol:AT-compatible computer with 200 MHz Pentium® II (or better).



Windows® XP or Windows Vista® (32-bit) operating system.



High speed PCI serial card (or an unused PCI card slot). Computers purchasedfrom Princeton Instruments are shipped with the PCI card installed if High speed
PCI was ordered.



Minimum of 32 Mbytes of RAM for CCDs up to 1.4 million pixels. Collecting
multiple spectra at full frame or high speed may require 128 Mbytes or more ofRAM.

CD-ROM drive.

Hard disk with a minimum of 80 Mbytes available. A complete installation of the
program files takes about 17 Mbytes and the remainder is required for data
storage, depending on the number and size of spectra collected. Disk levelcompression programs are not recommended.

Super VGA monitor and graphics card supporting at least 256 colors with at least
1 Mbyte of memory. Memory requirement is dependent on desired display
resolution.

IEEE-488 GPIB port (required by DG535 Timing Generator, if present). May
also be required by Spectrograph.



Two-button Microsoft compatible serial mouse or Logitech three-button
serial/bus mouse.

USB 2.0 Protocol:AT-compatible computer with Pentium 3 or better processor and runs at 1 GHz or
better.



Windows XP (with Service Pack 3) or Vista (32-bit).



Native USB 2.0 support on the motherboard or USB Interface Card (Orange
Micro 70USB90011 USB 2.0 PCI is recommended)

Minimum of 256 Mb of RAM.



CD-ROM drive.

Hard disk with a minimum of 80 Mbytes available. A complete installation of the
program files takes about 17 Mbytes and the remainder is required for data

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storage, depending on the number and size of spectra collected. Disk levelcompression programs are not recommended.
Super VGA monitor and graphics card supporting at least 256 colors with at least
1 Mbyte of memory. Memory requirement is dependent on desired display
resolution.

IEEE-488 GPIB port (required by DG535 Timing Generator, if present). May
also be required by Spectrograph.



Two-button Microsoft compatible serial mouse or Logitech three-button
serial/bus mouse.

Operating Environment
Storage Temperature: < 55°C
Lab Temperature: 30°C > T > -25°C
Supplemental Cooling Water Flow Rate: 1-3 liters per minuteNote: Circulating water will enhance cooling performance but is not required.
Lab Humidity: < 50%; non-condensing.

Controller
Controller Type: ST-133
Inputs:EXT SYNC: TTL input (BNC) to allow data acquisition to be synchronized withexternal events. Sense can be positive or negative going as set in software.
Synchronization and Trigger Modes are discussed in the Shutter Mode and Gated
operation chapters.
Outputs:
VIDEO or AUX
Video: 1 V pk-pk from 75 , BNC connector. Either RS-170 (EIA) or CCIR
standard video as specified when system was ordered. Requires connection via
75  cable that must be terminated into 75 .
Aux: Reserved for future use.
: TTL output (BNC) for monitoring detector status. Logic output is softwareselectable as either NOT SCAN or SHUTTER. When the logic output is NOT
SCAN, it is at a TTL low when CCD is being read; otherwise high. When the
logic output is SHUTTER, the output precisely brackets shutter-open time
(exclusive of shutter compensation) and can be used to control an external shutter
or to inhibit a pulser or timing generator. Default selection is SHUTTER.
: TTL output (BNC); marks start of first exposure. When run is initiated,remains high until completion of cleaning cycles preceding first exposure, thengoes low and remains low for duration of run.

Appendix A

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187

SERIAL COM: Data link to computer via proprietary cable connected to this 9-pin“D” connector. Cable lengths to 165 feet (50 m) available. An optional fiber
optic link is available to extend the distance to ~3300 feet (1 km).
USB 2.0: Data link to computer via USB cable inserted at this connector. Cable
length of 5 meters is standard. Other lengths may be available. Contact Customer
Service for more information.
TTL I/O: 8 TTL Inputs and 8 TTL Outputs are provided for control via the TTL
connector. Refer to Chapter 13, "TTL Control" for more information.
A/D Converters
Standard: 16-bit, 100 kHz readout rate only.
Optional: Dual digitizers with either 100 kHz/1 MHz, 50 kHz/1 MHz, or
1 MHz/5MHz readout rates. Software-selectable. Low-speed operation gives better
noise performance; high-speed operation allows faster data acquisition.
Linearity: better than 1%.
Readout noise: 1-1.2 counts RMS on standard controllers.
Shutter Compensation TimeThe following numbers apply for a 1 MHz ST-133.
Shutter

Compensation Time

Electronic

6 ms

None

0 ns

Miscellaneous
Dimensions: See Appendix B.
Controller Weight:
ST-133A: 13 lb (5.9 kg)
ST-133B: 12.5 lb (5.7 kg)
Power Requirements: Nominally 100, 120, 220 or 240 VAC. Refer toFuse/Voltage label on rear of Controller for details. Required DC voltages are
generated in the controller. Power to detector is supplied via controller cable.
Environmental Requirements:
Storage temperature: -20 C to 55 C;
Operating temperature: 5ºC to +30ºC; For NTE/NTE 2 Detectors, theoperating temperature range over which specifications can be met is18 C to 23 C
Relative humidity: <50% noncondensing.
TTL Requirements: Rise time  40 ns, Duration  100 ns.

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The PI-MAX incorporates an internal gate pulse generator and high voltage power supply
controlled from an external timing generator, either a PTG or a Stanford Research DG535
Digital Delay/Pulse Generator. The DG535 is controlled from the application software
via a GPIB link.
Note: A DG535 purchased as part of a PI-MAX system will have the Inhibit input
enabled. If you are going to operate the PI-MAX with a DG535 that hasn’t had this input
enabled, it will be necessary to modify the DG535 as required. The modification is
simple and can be easily be made by any qualified technician. Contact the factory fordetails.
Gating Speed
Fast Gate Intensifier
Gen II 18 mm: <5 ns FWHM in Start/Stop mode
Gen II 25 mm: <7 ns FWHM
Gen III 18 mm: <10 ns FWHM in Start/Stop mode.
Slow Gate 18 mm: <50 ns FWHM
Slow Gate 25 mm: <100 ns FWHM
Fixed Fast:<2 ns FWHM - 18 mm Gen II<5 ns FWHM - 18 mm Gen III

Propagation Delay: 12 ns. Note that this is only the delay of the internal pulser. The
timing generator’s insertion delay, 25 ns for the PTG, 85 ns for the Stanford
Research DG535, must be considered as well.
Jitter: <100 ps
Maximum Repetition Rate (photocathode)Sustained: 50 kHz in variable mode; 5 kHz @ 2 ns
Burst: 250 kHz (bursts of 50 pulses)
Maximum Repetition Rate (MCP bracket pulsing): 5 kHz, (drops pulses if input
rate exceeds 5 kHz)
Start/Stop Inputs: Both are 0 to +5V rising edges, 50 , compatible with the Stanford
Research DG535 and applied via Timing Gen connector.
MCP Bracket Pulsing: MCP requires 500 ns to gate On and 200 ns to gate Off.
Note: Bracket pulsing only applies to units having a Gen II Image Intensifier. In
the case of units having a Gen III Image Intensifier, bracket pulsing does not
apply.

Appendix B
Outline Drawings
Note: Dimensions are in inches and [mm] unless otherwise noted.

PI-MAX/PI-MAX2

Figure 109. Outline Drawing: PI-MAX/PI-MAX2 with C-mount Adapter

Figure 110. Outline Drawing: PI-MAX/PI-MAX2 with F-mount Adapter

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Figure 111. Outline Drawing: PI-MAX/PI-MAX2 with Spectroscopy-mount Adapter

ST-133A Controller

Figure 112. Outline Drawing: ST-133A

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Appendix B

Outline Drawings

ST-133B Controller

Figure 113. Outline Drawing: ST-133B

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Appendix C
SoftwareIntroduction
The PI-MAX camera requires software control and can be operated with either of two
Princeton Instruments WinX application programs, WinView/32 or WinSpec/32. Somecamera parameters are controlled via the Controller. Others are controlled via the DG535
Timing Delay Generator, which is required for gated operation of the camera. The
software manuals discuss control of the PI-MAX, PTG and DG535 in detail.
Nevertheless, the following paragraphs, which delineate the applicable software screens,
may prove helpful as a convenient reference.

Camera State

Figure 114. Camera State dialog

In a system having the PI-MAX camera, this dialog appears when the software is booted.
It displays the camera's current start-up state and allows you to restore the previous
setting.
Keep in Safe Mode: This is the default. Whenever the software is booted, the Safe
mode is established, biasing the PI-MAX intensifier’s photocathode off. The
intensifier gain and exposure time in effect when the software was last shut down
are retained.
Restore to Last Setting: Making this selection followed by clicking on OK will put
the camera in the gate mode in effect when the software was last shut down.
Thus, clicking on the Restore to Last Setting radio button could put thecamera in Safe Mode, Shutter Mode or Gate Mode, whichever was theactive state at the time of shutdown. In addition, the intensifier gain in effectwhen the software was shut down is also restored, as is the exposure time.
Once the selection has been made, the user can easily change the gate mode via theExperiment Setup Main page. In systems having the PI-MAX camera, the Experiment Setup
Main page allows the user to directly select Safe mode, Shutter Mode or Gate Mode.

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Main tab(Experiment Setup on Acquisition menu)

Figure 115. Main tab with PI-MAX camera

The Experiment Setup Main tab is used to specify the most essential parameters. These
include the Exposure Time, Number of Images, Number of Accumulations and choice ofFull Chip or Region of Interest readout. Some of the selections on this page only apply
for a PI-MAX camera. With other cameras these selections are not displayed. Selections
unique to the PI-MAX include.
Amplifier: If the PI-MAX is equipped with the Thomson 512 × 512 CCD array, eitherof two amplifier output nodes are automatically selected depending on the A/D
speed. The FAST (1 MHz) A/D selection uses the fast node, while the SLOW
(500 kHz or slower) A/D uses the slow (low-noise) node. The default setting isread from non-volatile RAM in the PI-MAX. If the selection is changed, the new
setting is written to the non-volatile RAM and becomes the new starting default.
Fast node: Allows the camera to collect 16-bit images at a readout rate of up to
1 million pixels per second.
Low Noise node: When operating at a lower speed, the camera provides
superior noise performance.
Intensifier:Gain: Sets the intensifier gain when operating with a PI-MAX intensified
camera. The range is in arbitrary units from 0 to 255 and the default setting,which will give good results in many applications, is 128.

Appendix C

Software195

Shutter Mode: Selecting this radio button biases the PI-MAX photocathodecontinuously on during the exposure time and off during readout. This mode
works with exposure times as short as 5 ms.
Gate Mode: Selecting this radio button puts PI-MAX in Gate mode, in which
the photo-cathode is biased on by pulses generated in the DG535.
Safe Mode: Selecting this radio button puts PI-MAX in the Safe mode, inwhich the photocathode is continuously biased off until either Shutter Mode orGate Mode is selected. Note that Safe mode is the turn-on default. In a systemhaving the PI-MAX camera, when the software is booted, a dialog appears thatallows you to change the PI-MAX start-up gate mode.

Pulsers dialog

Figure 116. Pulsers dialog

The Pulsers dialog, which opens when Pulsers is selected on the Setup menu, allows theuser to choose whether the software is configured to run a PG200 Pulser, a PTG module,a DG535 Timing Delay Generator, or no pulser. To the right of the pulser-selection
buttons is the Setup button that gives access to the pulser setup screens. Select PTG or
DG535 for operation with the PI-MAX (PG-200 is not compatible with the PI-MAX).

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PTG dialog

Figure 117. PTG dialog

Operation of the PTG (ProgrammableTiming Generator) becomes available when you
select Pulsers from the Setup menu, next click on the PTG radio button and then clickon the Setup PTG button. This opens the PTG dialog as shown above. Note that pulser
support must be selected when installing the WinX application software (WinView/32 or
WinSpec/32) for PTG control to be available, and that the intended use of the PTG is for
operation in conjunction with the PI-MAX CCD Detector.
The choices provided by the Triggers, Gating, and Aux Trig Out tabs are described in
the WinX application software Help topics.

DG535 dialog

Figure 118. DG535 dialog

Appendix C

Software197

Operation of the DG535 Timing Generator becomes available when you select Pulsers
from the Setup menu, next click on the DG535 radio button and then click on the Setup
DG535 button. This opens the DG535 dialog as shown above. Note that pulser support
must be selected when installing the WinX application software (WinView/32 or
WinSpec/32) for DG535 control to be available, and that the intended use of the DG535
is for operation in conjunction with the PI-MAX CCD Detector.
The DG535 parameters are set via the IEEE-488 GPIB link between the computer and theDG535 Pulser. The choices provided by the Triggers, Gating and Comm Port tabs
correspond to those provided by the DG535 front panel, and are described in the WinX
application software Help topics and in the DG535 manual.

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Appendix D
C-Mount and F-Mount Adapters
Attaching the C-Mount or F-Mount Adapter to the PI-MAX
The PI-MAX is supplied with the lens mount adapter specified when the system wasordered, normally either for a screw-type C-mount lens or for a bayonet type F-mount lens,allowing a lens of the corresponding type to be mounted quickly and easily. If you havemultiple mount adapters and you want to change from one adapter type to another: loosen
the three setscrews, unscrew the current adapter, screw in the new adapter until it bottoms
out, and secure the adapter with the locking setscrews. The focal length distance willautomatically be correct to a high degree of precision.
The PI-MAX nose and imaging mounts are illustrated on the following pages.

Figure 119. PI-MAX Standard Nose

Figure 120. C-Mount Adapter

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Figure 121. F-Mount Adapter

Mounting the Lens
C-mount lenses simply screw clockwise into the threaded lens mount at the front of thecamera. In mounting a C-mount lens, tighten it securely by hand (no tools).
To mount an F-mount lens on the camera (Figure 122), locate the large indicator dot on
the side of the lens. There is a corresponding dot on the front side of the camera lens
mount. Line up the dots and slide the lens into the mount. Then turn the lenscounterclockwise until a click is heard. The click means that the lens is now locked inplace.

Figure 122. F-mount (Nikon) Lens Adapter

Removing either type lens is equally simple. In the case of a C-mount lens, rotate the lenscounterclockwise until it is free of the mount. In the case of an F-mount lens, press thelocking lever on the mount while rotating the lens clockwise until it comes free and canbe pulled straight out.

Appendix D

C-Mount and F-Mount Adapters

201

Both types of lenses typically have provisions for focusing and aperture adjustment, withthe details varying according the make and model of the lens.

WARNING Always begin with the lens stopped all the way down (largest f/ stop number) tominimize the risk of overloading the intensifier.

Mounting Orientation
The PI-MAX can be mounted at any attitude or angle. The camera can rest on any securesurface. Take care not to block the ventilation openings.

WARNING In the case of cameras equipped with F-mount, do not mount the camera in the nose-up
operation where the lens mount would be required to hold the camera’s weight. The
F-mount is not designed to sustain the weight of the camera in this orientation and thecamera could pull free. You must provide additional support for the camera.

Should the camera be mounted in the nose-up position beneath a table, take care toprotect the mounting components from lateral stresses, such as might occur should
someone accidentally bump the camera with a knee while working at the table. One
solution to this problem would be to install a barrier between the camera and operator toprevent any accidental contact.
There are no special constraints on nose-down operation. Again, however, good operating
practice might make it advisable to take steps to prevent accidental contact from unduly
stressing the mounting components.

WARNING Always begin with the lens stopped all the way down (largest f/ stop number) tominimize the risk of overloading the intensifier.

Focusing
There is no difference between focusing considerations for an F-mount lens and a
C-mount lens. Simply rotate the lens-focusing ring for the sharpest observed image. The
lens will show maximum focus sensitivity at full aperture (lowest f-stop setting). Oncethe point of optimum focus is obtained, you may wish to adjust the lens aperture to f/8 or
f/11, that is, somewhere near mid-range aperture, where the lens will probably be sharper
than it is with the lens aperture completely open. Some readjustment of the Exposure
Time may be required to achieve the most pleasing image. In microscopy applications, itwill also be necessary to review the discussions in Chapter 12.

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Appendix E
Spectroscopy-Mount and Spectrograph
Adapters
Spectroscopy-Mount Adapter
The PI-MAX is supplied with a spectroscopy-mount adapter if one was specified when thesystem was ordered. The spectroscopy-mount adapter is simply screwed directly into thenose and then secured by three set screws. If you want to change from one adapter type toanother (e.g., C-mount to spectroscopy-mount), loosen the three setscrews, unscrew thecurrent adapter, screw in the new adapter until it bottoms out, and secure the adapter withthe locking setscrews. The focal length distance will automatically be correct to a highdegree of precision. However, there will be the usual focal depth adjustment androtational adjustment at the spectrograph input or output.

Figure 123. PI-MAX Standard Nose

Figure 124. Spectroscopy-Mount Adapter

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Version 5.GSpectrograph Adapters
Princeton Instruments offers a variety of spectrograph adapters for mounting a PI-MAX
to a spectrograph: Acton (adapters are available for all Acton models), the ISA HR320,
ISA HR640, Chromex 250IS, and most instruments that are 1 meter or longer. (If you are
not sure of the depth of the exit focal plane, contact the spectrograph manufacturer.)
Mounting the camera to one of these spectrographs typically requires a female Focusing
Flange that may be a separate part or an integral part of the spectrograph. Also required is amale Focusing Flange that slides into the female flange to set the focus and which is bolted
to the spectroscopy-mount adapter that screws into the PI-MAX nose.
The mounting instructions for spectrograph adapters offered by Princeton Instruments
are organized by spectrograph model and adapter kit number. For the appropriate
instruction set, see Table 14, page 205, which cross-references these items with thepage number.
Note: When mounted to a spectrograph, the text on the back of the PI-MAX shouldbe right side up.

Spectrograph-Detector Focusing
The detector mounting hardware provides two degrees of freedom: focus and rotation.
In this context, focus means to physically move the detector back and forth through the
focal plane of the spectrograph. The approach taken is to slowly move the detector in andout of focus and adjusting for optimum while watching a live display on the monitor,
followed by rotating the detector and again adjusting for optimum. The following
procedure, which describes the focusing operation with an Acton 2300i spectrograph, canbe easily adapted to other spectrographs.
1. Mount a light source such as a mercury pen-ray type in front of the entrance slit of
the spectrograph. Any light source with line output can be used. Standard fluorescent
overhead lamps have good calibration lines as well. If there are no “line” sources
available, it is possible to use a broad band source such as tungsten for the alignment.
If this is the case, use a wavelength setting of 0.0nm for alignment purposes.
2. With the spectrograph properly connected to the controller, turn the power on, wait
for the spectrograph to initialize. Then set it to 435.8 nm if using a mercury lamp or
to 0.0 nm if using a broadband source.
Hint: Overhead fluorescent lights produce a mercury spectrum. Use a white card
tilted at 45 degrees in front of the entrance slit to reflect overhead light into thespectrograph. Select 435.833 as the spectral line.
3. Set the slit to 25 µm. If necessary, readjust the Exposure Time to maintain optimum(near full-scale) signal intensity.
4. Slowly move the detector in and out of focus. You should see the spectral line gofrom broad to narrow and back to broad. Leave the detector set for the narrowest
achievable line.
Note that the way focusing is accomplished depends on the spectrograph, as follows.
Long focal-length spectrographs such as the Acton 2300i: The
mounting adapter includes a tube that slides inside another tube to move thedetector in or out as required to achieve optimum focus.

Appendix E

Spectroscopy-Mount and Spectrograph Adapters

205



Short focal-length spectrographs: there is generally a focusing mechanismon the spectrograph itself which, when adjusted, will move the optics as required
to achieve proper focus.

No focusing adjustment: If there is no focusing adjustment, either provided
by the spectrograph or by the mounting hardware, then the only recourse will beto adjust the spectrograph’s focusing mirror or to shim the detector.

5. Next adjust the rotation. You can do this by rotating the detector while watching alive display of the line. The line will go from broad to narrow and back to broad.
Leave the detector rotation set for the narrowest achievable line.
Alternatively, take an image, display the horizontal and vertical cursor bars, andcompare the vertical bar to the line shape on the screen. Rotate the detector until theline shape on the screen is parallel with the vertical bar.
Note: When aligning other accessories, such as fibers, lenses, optical fiber adapters, firstalign the spectrograph to the slit. Then align the accessory without disturbing the detector
position. The procedure is identical to that used to focus the spectrograph, i.e. do thefocus and alignment operations while watching a live image.
Spectrograph

Adapter Kit No.

Page

Acton

Sliding Tube

206

Acton

C-Mount Adapter

207

Chromex 250 IS

7050-0090

208

ISA HR 320

7050-0010

209

ISA HR 640

7050-0034

210

SPEX 270M

7050-0041

211

SPEX 500M

7050-0038

212

SPEX TripleMate

7050-0007

213

Table 14. Spectrograph Adapters

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Acton (Sliding Tube)

1.

Qty

P/N

3

2826-0120

Description
Screw, 10-32  1/2, Hex Head, Stainless Steel

Assembly Instructions
1. Make sure that the shipping cover has been removed from the detector port on the
spectrograph.
2. Loosen the setscrews holding the Acton adapter in the spectrograph and remove theadapter. If there is a spacer plate installed on the adapter, remove it.
3. Leaving 1/4" of thread exposed, mount the three (3) hex head screws to the adapter.
4. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
5. Tighten the screws.
6. Gently insert the adapter into the spectrograph and fasten with the setscrews.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

Appendix E

Spectroscopy-Mount and Spectrograph Adapters

207

Acton (C-Mount Adapter)

Qty

P/N

Description

1.

1

8401-071-01 Adapter Plate

2.

1

8401-071-02 Threaded C-Mount Adapter

3.

32826-0127

Screw, 10-32  1/4, Button Head Allen Hex, Stainless Steel

Assembly Instructions
1. Make sure that the shipping cover has been removed from the detector port on the
spectrograph.
2. Loosen the setscrews holding the sliding tube in the spectrograph and remove thetube. If there is a spacer plate installed on the sliding tube, remove it.
3. Place the flat side of the adapter plate against the face of the detector.
4. Insert the threaded C-mount adapter through the center hole in the plate and screw
the adapter into the detector’s C-mount.
5. Using three (3) 1/4" long button head screws, secure the sliding tube to the adapter
plate.
6. Gently insert the sliding tube into the spectrograph and secure it with the setscrews.
Note: Adapter parts are machined to provide a tight fit. It may be necessary to rotate thedetector back and forth when inserting the sliding tube into the spectrograph. Forcing the tube
into the spectrometer could permanently damage the tube and the spectrometer opening.

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Chromex 250 IS

Qty

P/N

Description

1.

12517-0901

Plate, Adapter-Female

2.

42826-0283

Screw, 10-32  3/4, Socket Head, Stainless Steel, Hex, Black3.

12518-0227

Adapter-Male, ICCD Diode Array

4.

32826-0120

Screw, 10-32  1/2, Hex Head, Stainless Steel

5.

12826-0082

Set Screw, 10-32  1/4, Stainless Steel, Allen Hex, Nylon Tip

Assembly Instructions
1. Attach part 1 to the spectrograph wall (dashed line in illustration) with the socket
head screws provided.
2. Leaving 1/4" of thread exposed, mount the three (3) hex head screws to part 3.
3. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
4. Tighten the screws.
5. Gently insert part 3 into part 1 and fasten with the setscrew.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

Appendix E

Spectroscopy-Mount and Spectrograph Adapters

209

ISA HR 320

Qty

P/N

Description

1.

12518-0044

Flange-Female, Mechanical, ISA, HR3202.

32826-0053

Screw, 10-32  7/16, Socket Head Cap Hex, Stainless Steel

3.

12518-0045

Flange-Male, Detector Mate

4.

32826-0120

Screw, 10-32  1/2, Hex Head, Stainless Steel

5.

12826-0082

Set Screw, 10-32  1/4, Stainless Steel, Allen Hex, Nylon Tip

Assembly Instructions
1. Attach part 1 to the spectrograph wall (dashed line in illustration) with the socket
head screws provided.
2. Leaving 1/4" of thread exposed, mount the three (3) hex head screws to part 3.
3. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
4. Tighten the screws.
5. Gently insert part 3 into part 1 and fasten with the setscrew.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

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ISA HR 640

Qty

P/N

Description

1.

12518-0203

Adapter-F, HR-640

2.

42826-0144

Screw, M4x.7x14 mm, Socket Head, Hex, Stainless Steel

3.

12518-0227

Adapter-Male, ICCD Diode Array

4.

32826-0120

Screw, 10-32  1/2, Hex Head, Stainless Steel

5.

22826-0082

Set Screw, 10-32  1/4, Stainless Steel, Allen Hex, Nylon Tip

Assembly Instructions
1. Attach part 1 to the spectrograph wall (dashed line in illustration) with the socket
head screws provided.
2. Leaving 1/4" of thread exposed, mount the three (3) hex head screws to part 3.
3. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
4. Tighten the screws.
5. Gently insert part 3 into part 1 and fasten with the setscrews.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

Appendix E

Spectroscopy-Mount and Spectrograph Adapters

211

SPEX 270M

Qty

P/N

Description

1.

12518-0691

Female Adapter Plate, 2.400 ID

2.

62826-0068

Screw, 6-32  3/8. Socket Head, Hex, Stainless Steel

3.

12518-0690

Adapter Male, Focusing, Male, Spec 270

4.

32826-0120

Screw, 10-32  1/2, Hex Head, Stainless Steel

5.

22826-0019

Set Screw 8-32  3/16, Hex, Nylon Tip

Assembly Instructions
1. Attach part 1 to the spectrograph wall (dashed line in illustration) with the socket
head screws provided.
2. Leaving 1/4" of thread exposed, mount the three (3) hex head screws to part 3.
3. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
4. Tighten the screws.
5. Gently insert part 3 into part 1 and fasten with the setscrews.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

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SPEX 500M

Qty

P/N

Description

1.

12517-0214

Adapter-Female, Spex 500M

2.

82826-0170

Screw, 1/4-20  0.5L, Low Socket Head Cap

3.

12518-0291

Adapter Male, Spex 500M

4.

32827-0010

10-32 Nut, Stainless Steel

5.

32826-0120

Screw, 10-32  1/2, Hex Head, Stainless Steel

6.

22826-0055

Set Screw 8-32  1/4, Allen Hex, Nylon Tip

Assembly Instructions
1. Attach part 1 to the spectrograph wall (dashed line in illustration) with the socket
head screws provided.
2. Leaving 1/4" of thread exposed, mount the three (3) hex head screws and nuts topart 3.
3. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
4. Tighten the screws.
5. Gently insert part 3 into part 1 and fasten with the setscrews.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

Appendix E

Spectroscopy-Mount and Spectrograph Adapters

213

SPEX TripleMate

Qty

P/N

Description

1.

12518-0183

Adapter-Male, ICCD/For Spex TripleMate

2.

42826-0128

Screw, 10-32  5/8, Socket Head Cap, Stainless Steel

3.

12517-0163

Slit Mount, Spex

4.

42826-0129

Screw, 1/4-20  3/4, Socket Head Cap, Stainless Steel

5.

32826-0120

Screw, 10-32  1/2, Hex Head, Stainless Steel

6.

12518-0185

Adapter-Female, Flange Spex

7.

22826-0070

Set Screw, 6-32  3/16, Stainless Steel, Allen Hex

1

2500-0025

O-ring, 2.359x.139, Viton (installed)

12500-0026

O-ring, 2.484x.139, Viton (installed)

Assembly Instructions
1. Mount the whole assembly onto the spectrograph (dashed line in illustration).
2. Leaving 1/4" of thread exposed, mount the three (3) hex head screws to part 1.
3. Mount the adapter to the detector flange and rotate the adapter so the screw heads areover the narrow end of the slots.
4. Tighten the setscrews.
5. Tighten the hex head screws.
Note: Adapter parts are machined to provide a tight fit. It is necessary to rotate the detector
back and forth when inserting into the spectrograph adapter. Do not force the two parts of theadapter together, as they can be permanently damaged by excessive force.

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Appendix F
IVUV Detector
Introduction
The Intensified Vacuum UV Detector (IVUV), a variation of the PI-MAX detector, isavailable in two types. The first type is a sealed-nose version that is backfilled with dry
nitrogen only. The second type is an open-nose version that must be purged with dry
nitrogen during operation.

WARNING

Under normal conditions, the front end of the sealed-nose IVUV is sealed and backfilledwith dry nitrogen only so there is no danger of damage due to condensation. In the caseof an open-nose IVUV, however, the detector must be purged with dry nitrogen during
operation. Otherwise catastrophic damage could occur that would not be covered by the
Warranty.

Nitrogen Purging of the Detector

Figure 125. Camera’s Purge Warning Label

An IVUV requires continuous purging of the detector with nitrogen while operating
cooled. Even if the detector is not powered, it must be purged whenever water or othercoolant is circulating, as the possibility of condensation still exists. See Chapter 3 foradditional information concerning circulating coolant.

WARNING Never use any gas other than dry nitrogen. Noble gases, such argon or helium, have a low
breakdown voltage, which could lead to arcing that could destroy the image intensifier.

CautionIf the relative humidity in your lab is high, e.g., > 40% do not operate the open-nosedetector without purging, even if you are not cooling the detector!

Dryness Requirement
The dryness of the nitrogen is critical. The colder the detector is operated, the dryer thegas must be. Also, the longer the detector is operated cold, the drier the gas must be.
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Be wary of unspecified “dry” gases intended for less demanding applications. Even a
99.9% pure gas can deposit enough water to cause permanent damage to the detector.
As an example, consider an IVUV camera where the CCD temperature is -20°C andwhere you are using nitrogen with 100 ppm of water vapor. This water vapor will be at
dew point and water will condense and freeze on the CCD. Ice will continue to form foras long as this nitrogen flows over the surface of the CCD.
Princeton Instruments recommends that gases with less than 10 ppm water vapor be used.
An example is AIRCO compressed nitrogen grade 4.8 (3 ppm). Equivalent gases fromother quality vendors are also suitable.
Connect the nitrogen source to the nitrogen inlet on the upper surface of the camera nose.
Purge the detector for at least 10 minutes at a high rate (1-2 liters/minute). Then lower therate to 750-1000 ml/minute.

Caution

After you have finished an experiment and have turned off the controller, maintain a gas
flow of at least 2 liters/minute for at least 15 minutes. This keeps condensation fromforming on the detector until it reaches room temperature.

Backfilling
If a sealed version of the IVUV PI-MAX detector must be backfilled, contact the factory
and arrange to return the detector to the factory where it can be properly flushed,backfilled and resealed again. See page 232 for contact information.

WARNING

Operating a sealed-nose IVUV PI-MAX that is no longer backfilled with dry nitrogenmay result in condensation on the array that could cause irreversible damage. Suchdamage would not be covered by the Warranty.

Appendix G
USB 2.0 Limitations
The following information covers the currently known limitations associated with
operating under the USB 2.0 interface.
Maximum cable length is 5 meters (16.4 feet)

1 MHz is currently the upper digitization rate limit for the ST-133 Controller.



Large data sets and/or long acquisition times may be subject to data overrun
because of host computer interrupts during data acquisition.

USB 2.0 is not supported by the Princeton Instruments PC Interface Library (EZDLLS).



Some WinX (WinView/32 and WinSpec/32) 2.5.X features are not fully
supported with USB 2.0. See the table below.
FeatureDemo Port Capability

Supported with USB 2.0 in
WinX 2.5.X

RemarksNO

DIF
Kinetics

YES

WinX 2.5.18.1

Reset Camera to NVRAM
Defaults

NO

Temperature Lock Status

YES

PTG

YES

Virtual ChipNO

Custom Timing

YES

WinX 2.5.18.1

Custom Chip

YES

WinX 2.5.18.1

Frames per Interrupt

NO

RS170 (Video Output)

NO

Online Exposure

NO

File Information

YES

Overlapping ROIsNO

WinX 2.5.x doesn’t utilize
hardware lock status

Not all header info iscurrently available in
WinX 2.5.x through
PVCAM

Table 15. Features Supported under USB 2.0 (continued on next page)

217

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PI-MAX/PI-MAX2 System Manual
FeatureVersion 5.G

Supported with USB 2.0 in
WinX 2.5.X

Remarks

Macro Record

YES

Macros recorded for nonPVCAM cameras may
have to be re-recorded tofunction

TTL I/ONO
Table 15. Features Supported under USB 2.0

Appendix H
Glossary
Binning: A process that may occur in the readout register and the output node (on-chipor hardware binning) or is performed as a post-process (software binning). Binningcombines charge from rectangular groups of adjacent pixels into super pixels. Whendone on-chip, this process reduces readout time and the burden on computer memory;the drawbacks are lowered resolution and the possibility of saturation and blooming.
Software binning avoids the problem of saturation and blooming.
Blooming: The spillover of excess charge into adjacent pixels.
Bracket Pulsing: See MCP Bracket Pulsing.
Burst Mode: PTG term. Used when a short burst of very rapid gate pulses is needed tosynchronize data acquisition with a high frequency signal of interest. Occurring
during the CCD array exposure time, a burst has a maximum repetition rate of
500 kHz, generating a high voltage pulse every 2 µs. The burst can be driven from anexternal trigger or from the internal oscillator.
CCD Array Dimensions and Pixel Size: Arrays that are square or nearly square are
typically used for imaging applications, while rectangular arrays are typically used inspectroscopy applications. The smaller the pixel size, the better the resolution, but the
pixel full-well capacity smaller. Conversely, the larger the pixel size, the poorer the
resolution, and the greater the pixel full-well capacity.
CCD Array Dynamic Range: The dynamic range of a CCD is the maximum achievablesignal divided by the camera noise, where the signal strength is determined by thefull-well capacity and noise is the sum of dark and read noises. The greater the
dynamic range , the better the CCD is able to detect differences between the dimmest
and brightest intensities in an image. The readout speed affects the dynamic range ofa pixel: the faster the speed, the higher the noise, and the smaller the dynamic range.
CCD Spectral Sensitivity: Coatings applied to the CCD input window can enhancesensitivity in the UV regions. Deep-depletion enhances sensitivity in the NIR.
Dark Charge or Dark Current: The thermally induced buildup of charge in the CCD
over time. Dark charge values vary widely from one CCD array to another and areexponentially temperature dependent. In the case of cameras that have MPP typearrays, the average dark charge is extremely small. However, the dark-charge
distribution is such that a significant number of pixels may exhibit a much higher
dark charge, limiting the maximum practical exposure. To minimize the collection ofdark charge, operate the camera at the lowest CCD temperature possible.
Since each CCD has its own dark charge pattern, unique to that particular device,acquiring and saving a dark charge "background image" under conditions identical tothose used to acquire the "actual" image and then subtracting that image from theactual image will significantly reduce dark-charge effects.
EBI: Equivalent Background Illumination. EBI comes from thermally-generated
electrons that cannot be distinguished from those generated by light photons. EBI can
219

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be reduced by cooling the intensifier (or environment) and is usually negligible in
gated applications.
Exposure Time: The period during which the ST-133 allows incoming signal tointegrate on the CCD array. For signal to be detected and integrated on the CCD
array, it must both fall in a valid gate width and in a valid exposure time.


In Shutter Mode, the exposure time is set on the Experiment|Timing dialog
and the photocathode is biased ON for that period.



In Gate Mode with a PTG, the exposure time is determined by a PTG pulse
ensemble defined by the PTG gating setup.



In Gate Mode with a DG535, an ET = 0 setting means that the exposure time
will be determined by the External Sync signal. An ET > 0 setting determines the
exposure time.
External Sync: Readout synchronization mode where the CCD array is synchronized toan external source, i.e., the array is scanned upon arrival of an external trigger pulse.
External Trigger mode: Trigger mode where gate pulses are delayed from external
input trigger pulses. Also a detector readout synchronization mode where the detector
is scanned continuously, i.e. Freerun mode, but data storage does not begin until thearrival of an external trigger pulse.
Frame: The area of the CCD array that is readout after an exposure time ends. For a
512x512 array, a full-frame would consist of the entire 512X512 pixel area. In the
WinX/32 software, the number of frames to be acquired during a data acquisition isdetermined by the Number of Images (or Number of Spectra) parameter on theExperiment Setup|Main tab. If the parameter value is greater than 1, multiple
frames of data will be acquired and stored in a single data file.
Note: Kinetics Mode results in multiple images/spectra (subframes) collected on asingle frame
Frame Rate (fps): The number of frames that can be readout per second. The effective
frame rate can be increased by defining a Region of Interest (ROI) that is smaller
than the full-frame size. This means that a selected portion of the image can bedisplayed and the remainder of the accumulated charge discarded. The frame rate
generally increases with reduction in the size of the detected area. For example, a
CCD with a sensor size of 1000 x 1000 and an output rate of ten frames/second can
produce 100 frames/second if the read-out region is reduced to 100 x 100 pixels.
Full-Well Capacity: The number of electrons that can be stored in a pixel. The smaller
the pixel, the fewer electrons can be stored; therefore, either the exposure times need
to be shorter or the signal intensity must be lower. Note that binning relies on the
full-well capacity of the pixels in the serial shift register and of the output node.
Typically, a serial shift register pixel has a full-well capacity that is 2 times greaterthan that of an image pixel and the output node has a full-well capacity that is about
1.5-2 times greater than that of a serial register pixel.
FWHM: Full width half-maximum. Time period from the mid-point of the leading edge
to the mid-point of the trailing edge of the gate pulse. Used to describe pulse width.
Gate Delay: The time between the beginning of the trigger pulse (either internal orexternal) and the beginning of the photocathode gate pulse.

Appendix H

Glossary

221

Gate Mode: PI-MAX intensifier mode in which the photocathode is biased on only forthe time that each gate pulse is applied. In this way, the array can be exposed tomultiple images during a single exposure time. As a result, the tolerance to room
light is higher in gated operation, but the risk of damaging overload from intenselight sources such as lasers remains. In fact, intense light sources in gatedexperiments can cause spot damage that would be undetected by the alarm circuit.
Gate Width: The time during which light will be detected by the intensifier, intensified,and applied to the CCD. Basically, the intensifier controls what the chip 'sees' during
the exposure time. For signal to be detected, it must both fall in a valid gate widthand in a valid exposure time.
Input Windows: The intensifier and the CCD array both have input windows.
MgF2 : High vacuum UV transmission (between 100 nm and 200 nm).
Quartz: Excellent transmission over 190 nm - 1100 nm.
Clear glass (BK7): Visible (400 nm -700 nm) and NIR (700 nm - 2500 nm).
Anti-Reflection (A/R) coatings may be added to input windows to reduce signal loss andglare caused by reflection.
Intensifier-CCD Coupling: Transmission of the emitted photons is either through afiberoptic bundle or with a lens. The drawback to lens coupling is lower throughput(5%-10%) and increased stray light in the camera system. The advantages are that theintensifier can be removed and the camera can be used as a standard CCD imager
conversely an intensifier can be added to an existing camera.
Fiberoptic coupling results in a throughput of >60%, are capable of sensitivities
approaching single-photoelectron detection, and have a much better signal-to-noise
ratio (SNR) than lens-coupled devices. Disadvantages are that the fiberoptic bundle
is permanently attached to the CCD array and that the camera must be operated in adry, non-vacuum inert environment.
Intensifier Gating Speed: Temporal resolution in a PI-MAX is made possible byswitching the intensifier on and off (gating) very rapidly. Typical fast-gate
intensifiers have minimum gate widths (FWHM=full width at half-maximum gate
pulse) of approximately 2 ns. For slow-gated devices the FWHM is about 50 ns.
Fast-gating is achieved by adding a nickel (Ni) underlayer to photocathode. However,this layer may produce an effective QE reduction of as much as 40%. Slow-gate
intensifiers have neither the Ni layer nor its effects on QE.
Intensifier On/Off Ratio: The ratio of light output when the intensifier is gated on andoff: The higher the ratio, the better the gating. A high on/off ratio is necessary toeliminate the background and to faithfully reproduce transient events. In the visible
region on/off ratios exceeding 106:1 is typically achieved. In the UV region, theon/off ratio is typically much poorer (104:1) though with MCP Bracket Pulsing (seepage 85) ratios in the UV region can be improved dramatically (107:1).
Intensifier Size: 18 mm dia. and 25 mm dia. Generally speaking, the larger diameter
gives a larger field of view at the surface of the CCD array. The coupling of theintensifier to the CCD array is also a factor in determining the field view. A
fiberoptic reducing taper of 1.27:1 will increase the field of view, while a taper of 1:1
will have no effect.

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Intensifier Types:
Gen I: Obsolete. Developed in the early 1960's. Used electrostatic focusing andelectron acceleration to achieve signal gains up to 150. These intensifiers could detect
images under ambient light intensity as low as .01 lux. Problems included image
distortion, short-lived components, and large size.
GenII: Introduced in the late 1960's and early 1970's. Incorporated MCPs withresulting signal gain improvement (up to 20,000). Not as efficient as Gen I
intensifiers however have high resolution, no image distortion, and are small. Can
detect images under ambient light intensity as low as .001 lux.
Super Gen II: Gen II devices that employ novel photocathodes with extended
spectral range or high QE in a particular wavelength.
Gen III: Gen II technology with GaAs added as the photocathode coating. Highly
sensitive in the NIR region above 800 nm but relatively insensitive in the blue/green
region. Utilizes high-resolution MCPs (6 µm diameter channels) and ion-barrier
films. 2-3 orders of magnitude more sensitive to light than Gen II devices. Can detect
images under ambient light intensify as low as .0001 lux.
Gen IV: Introduced in 1999. No ion barrier film and exhibit enhanced QE, SNR,
dynamic range, and high-light-level resolution.
Internal Trigger mode: PTG or DG535 mode where gate pulses are delayed fromtrigger pulses produced by an internal timer. Delays are programmable in incrementsof 10 ns instead of 1 ns as they are in External Trigger mode.
Kinetics Mode: An optional PI-MAX mode of operation in which most of the CCD ismechanically or optically masked, leaving a small section (i.e., window) open tolight. A series of images is rapidly acquired during a single data acquisition period byrepeatedly gating the intensifier. The image is collected in the window while theintensifier is gated on, and after it is gated off, the image is shifted on the array toclear the window for the next image. After the entire series is collected, the CCD is
readout. Kinetics mode takes advantage of the fact that shifting on the array is much
faster than performing a readout.
lp/mm: line pairs per millimeter. A measure of resolution based on the ability of theimaging system to differentiate between two parallel lines. The higher the value, thefiner the resolution.
MCP: MicroChannel Plate. Composed of cylindrical channels through which electrons
from the photocathode travel and generate additional electrons, resulting in electron
gain. At the output of the MCP is a phosphor-coated fluorescent screen that converts
the electrons to photons that subsequently strike the CCD array and generate charge
in the array pixels.
MCP Bracket Pulsing: Available for PI-MAX cameras with Gen II intensifiers. This
technique enhances the intensifier's on/off ratio in UV measurements byautomatically adjusting the on/off switching of the MCP to bracket the photocathodegate pulse. By switching off the MCP, unwanted UV signal that strikes thephotocathode (even though gated off) is prevented from passing through the MCP tointegrate on the CCD array.

Appendix H

Glossary223

MCP Gating: Available for PI-MAXMG cameras. Applies the primary gating pulse to the
MCP portion of the tube and, if chosen by the user, applies the bracket pulse to thephotocathode.
MCP Resolution: The MCP is a slightly conductive glass substrate with millions ofparallel traversing channels containing a secondary electron emitter on their innerwalls. The smaller the diameter and more tightly grouped the channels, the higher the
resolution.
Phosphor Type: A phosphor is a chemical substance that fluoresces when excited by xrays, an electron beam, or ultraviolet radiation. Phosphors usually emit green lightwith decay times ranging from hundreds of nanoseconds to a few milliseconds. P43
offers high resolution (3 ms decay) while P46 offers fast decay for high-repetition
rate spectroscopy (3 µs decay). The shutter compensation time (see below), inserted
between the end of the exposure time and the beginning of the array readout, allows
for the decay time.
Photocathode Coatings: Coatings on the photocathode convert a portion of the incident
photons into electrons. Any photons that are not captured by the photocathode arelost from the final signal produced by the intensifier. Therefore, the kind of coating
and the resulting QE of the photocathode is very important. The choice of coating
determines the most effective spectral range for the intensifier. For example GaAs
(gallium arsenide) has high QE in the VIS and NIR regions. Multi-alkali coatings
have fair photoconversion in the visible (VIS) and ultraviolet (UV) but haverelatively limited response in the near IR (NIR).
Pulse Ensemble: PTG term. Consists of a Gate Start pulse, a Gate Stop pulse, and an
Auxiliary pulse. At the end of the ensemble, the photocathode is gated off, shutter
compensation time elapses to allow for phosphor decay, and then the CCD array isreadout.
QE: Quantum Efficiency. The percentage of incident photons converted to electronic
charge. The throughput of the input windows, the spectral sensitivity of thephotocathode and the CCD array, the illuminated surface (front or back) of the CCD
array, the intensifier on/off ratio, the MCP resolution, the MCP gain, and theintensifier-CCD coupling all contribute to the total system QE.
RAM: Random Access Memory used to store data such as experiment parameters.
Region of Interest (ROI): A square or rectangular set of contiguous pixels on the CCD
array that is usually smaller than the full frame. Using an ROI to acquire data results
in a faster readout of the array since data from pixels outside of that ROI is discarded.
Safe Mode: PI-MAX intensifier mode in which the photocathode is continuously biased
off.
Saturation: Caused when a pixel well is completely filled with charge. Once a pixel issaturated, additional charge will spillover (bloom) into adjacent pixels. Ways to deal
with saturation include lowering the array temperature (to reduce the dark charge
component), shortening the exposure time (to reduce the signal component), anddecreasing the gain (also to reduce the signal component).
Scan or Scanning: The process of reading out the contents of a CCD array.
Shutter Compensation Time: This is the amount time inserted between the end of the
exposure time and the beginning of the array readout. For a PI-MAX, the appropriate

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choices of Shutter Type (Hardware Setup|Controller/Camera tab card) are"Electronic" and "None". When "Electronic" is selected, 6 ms is inserted to allow
time for the phosphor to decay: this choice is appropriate for a P43 phosphor. No
time is inserted when "None" is selected: this choice is appropriate for a P46
phosphor.
Shutter Mode: PI-MAX intensifier mode in which the photocathode is biased on atduring the exposure time and is biased off before the array is read out.
Timing Mode: A timing mode determines how data acquisition is synchronized with anexperiment. The timing modes associated with a PI-MAX system are: Free Run,
External Sync, External Sync with Continuous Cleans, and Internal Sync.
Vertical Shift Time (µs): Reports the speed (in microseconds) at which a single row will
be shifted vertically. This information is based on the value in the Vertical Shift box.
The higher the value in that box, the longer the vertical shift time. This information
appears for the Frame Transfer and Kinetics modes.
Vertical Shift: Determines the speed of the image transfer from the exposed area of anarray to the masked area. Setting a lower value increases the shift speed. A higher
value gives a slower shift. If the shift is too fast, not all of the charge will betransferred. If too slow, image smearing will be increased due to the exposure thattakes place while the transfer is in progress. The default value gives good results inmost measurements.
Window Size: Specifies the height of the window for Kinetics mode and should be equal
to the height of the unmasked area of the array. This value must be 1 or greater.

Declarations of Conformity
This section of the PI-MAX/PI-MAX2 system manual contains the declarations ofconformity for PI-MAX and PI-MAX2 systems. A system includes the PI-MAX or
PI-MAX2 camera with a Gen II or Gen III intensifier and an ST-133 Controller with orwithout PTG boards.

225

DECLARATION OF CONFORMITY
We,

ROPER SCIENTIFIC(PRINCETON INSTRUMENTS)

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08618
Declare under our sole responsibility, that the productST-133 CONTROLLER with PTG BOARD and
PI-MAX GEN II/GEN III CAMERA HEADS,To which this declaration relates, is in conformity with general safety requirement for electricalequipment standards:

IEC 1010-1:1990, EN 61010-1:1993/A2:1995
EN 55011 for Group 1, Class A, 1991,
EN 61326-1, 1997-03 (EN 61000-4-2, EN 61000-4-3, EN 61000-4-4,
EN 61000-4-5, EN 61000-4-6, EN 61000-4-11)
Which follow the provisions of the

CE LOW VOLTAGE DIRECTIVE 73/23/EEC
And
EMC DIRECTIVE 89/336/EEC.

Date: August 7, 2002
TRENTON, NJ(PAUL HEAVENER)
Engineering Manager

DECLARATION OF CONFORMITY
We,

ROPER SCIENTIFIC(PRINCETON INSTRUMENTS)

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619
Declare under our sole responsibility, that the productST-133 CONTROLLER with
PI-MAX GEN II and GEN III CAMERA HEADS,To which this declaration relates, is in conformity with general safety requirement for electricalequipment standards:

IEC 1010-1:1990, EN 61010-1:1993/A2:1995
EN 55011 for Group 1, Class A, 1991,
EN 50082-1, 1993 (EN 61000-4-2, EN 61000-4-3, EN 61000-4-4)Which follow the provisions of the

CE LOW VOLTAGE DIRECTIVE 73/23/EEC
And
EMC DIRECTIVE 89/336/EEC.

Date: August 7, 2002
TRENTON, NJ(PAUL HEAVENER)
Engineering Manager

DECLARATION OF CONFORMITY
We,

ROPER SCIENTIFIC(PRINCETON INSTRUMENTS)

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619
Declare under our sole responsibility, that the productST-133 16-BIT 5 MHz CONTROLLER with PI-MAX2 CAMERA,
To which this declaration relates, is in conformity with general safety requirement for electricalequipment standards:

IEC 1010-1:1990, EN 61010-1:1993/A2:1995,
EN 61326 for Class A, 1998,(EN 61000-4-2, EN 61000-4-3, EN 61000-4-4, EN 61000-4-5,
EN 61000-4-6, EN 61000-4-11), EN 61000-3-2:2000, andEN 61000-3-3:1995,
Which follow the provisions of the

CE LOW VOLTAGE DIRECTIVE 73/23/EEC
And
EMC DIRECTIVE 89/336/EEC.

Date: July 18, 2003
TRENTON, NJ(PAUL HEAVENER)
Engineering Manager

Warranty & Service
Limited Warranty
Princeton Instruments, a division of Roper Scientific, Inc. ("Princeton Instruments", "us","we", "our") makes the following limited warranties. These limited warranties extend tothe original purchaser ("You", "you") only and no other purchaser or transferee. We havecomplete control over all warranties and may alter or terminate any or all warranties at
any time we deem necessary.

Basic Limited One (1) Year Warranty
Princeton Instruments warrants this product against substantial defects in materials and /or workmanship for a period of up to one (1) year after shipment. During this period,
Princeton Instruments will repair the product or, at its sole option, repair or replace any
defective part without charge to you. You must deliver the entire product to the Princeton
Instruments factory or, at our option, to a factory-authorized service center. You areresponsible for the shipping costs to return the product. International customers should
contact their local Princeton Instruments authorized representative/distributor for repair
information and assistance, or visit our technical support page atwww.princetoninstruments.com.

Limited One (1) Year Warranty on Refurbished or Discontinued
Products
Princeton Instruments warrants, with the exception of the CCD imaging device (which
carries NO WARRANTIES EXPRESS OR IMPLIED), this product against defects inmaterials or workmanship for a period of up to one (1) year after shipment. During thisperiod, Princeton Instruments will repair or replace, at its sole option, any defective parts,
without charge to you. You must deliver the entire product to the Princeton Instruments
factory or, at our option, a factory-authorized service center. You are responsible for the
shipping costs to return the product to Princeton Instruments. International customers
should contact their local Princeton Instruments representative/distributor for repair
information and assistance or visit our technical support page atwww.princetoninstruments.com.

XP Vacuum Chamber Limited Lifetime Warranty
Princeton Instruments warrants that the cooling performance of the system will meet our
specifications over the lifetime of an XP style detector (has all metal seals) or Princeton
Instruments will, at its sole option, repair or replace any vacuum chamber components
necessary to restore the cooling performance back to the original specifications at no costto the original purchaser. Any failure to "cool to spec" beyond our Basic (1) year limited
warranty from date of shipment, due to a non-vacuum-related component failure (e.g.,
any components that are electrical/electronic) is NOT covered and carries NO
WARRANTIES EXPRESSED OR IMPLIED. Responsibility for shipping charges is as
described above under our Basic Limited One (1) Year Warranty.

229

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Sealed Chamber Integrity Limited 12 Month Warranty
Princeton Instruments warrants the sealed chamber integrity of all our products for aperiod of twelve (12) months after shipment. If, at anytime within twelve (12) months
from the date of delivery, the detector should experience a sealed chamber failure, allparts and labor needed to restore the chamber seal will be covered by us. Open chamber
products carry NO WARRANTY TO THE CCD IMAGING DEVICE, EXPRESSED ORIMPLIED. Responsibility for shipping charges is as described above under our Basic
Limited One (1) Year Warranty.

Vacuum Integrity Limited 12 Month Warranty
Princeton Instruments warrants the vacuum integrity of “Non-XP” style detectors (do nothave all metal seals) for a period of up to twelve (12) months from the date of shipment.
We warrant that the detector head will maintain the factory-set operating temperature
without the requirement for customer pumping. Should the detector experience a Vacuum
Integrity failure at anytime within twelve (12) months from the date of delivery all partsand labor needed to restore the vacuum integrity will be covered by us. Responsibility forshipping charges is as described above under our Basic Limited One (1) Year Warranty.

Image Intensifier Detector Limited One Year Warranty
All image intensifier products are inherently susceptible to Phosphor and/or Photocathodeburn (physical damage) when exposed to high intensity light. Princeton Instruments
warrants, with the exception of image intensifier products that are found to have
Phosphor and/or Photocathode burn damage (which carry NO WARRANTIESEXPRESSED OR IMPLIED), all image intensifier products for a period of one (1) year
after shipment. See additional Limited One (1) year Warranty terms and conditions
above, which apply to this warranty. Responsibility for shipping charges is as describedabove under our Basic Limited One (1) Year Warranty.

X-Ray Detector Limited One Year Warranty
Princeton Instruments warrants, with the exception of CCD imaging device and fiber
optic assembly damage due to X-rays (which carry NO WARRANTIES EXPRESSEDOR IMPLIED), all X-ray products for one (1) year after shipment. See additional Basic
Limited One (1) year Warranty terms and conditions above, which apply to thiswarranty. Responsibility for shipping charges is as described above under our Basic
Limited One (1) Year Warranty.

Software Limited Warranty
Princeton Instruments warrants all of our manufactured software discs to be free fromsubstantial defects in materials and / or workmanship under normal use for a period ofone (1) year from shipment. Princeton Instruments does not warrant that the function of
the software will meet your requirements or that operation will be uninterrupted or error
free. You assume responsibility for selecting the software to achieve your intended
results and for the use and results obtained from the software. In addition, during the one(1) year limited warranty. The original purchaser is entitled to receive free version
upgrades. Version upgrades supplied free of charge will be in the form of a downloadfrom the Internet. Those customers who do not have access to the Internet may obtain theversion upgrades on a CD-ROM from our factory for an incidental shipping and handlingcharge. See Item 12 in the following section of this warranty ("Your Responsibility") for
more information.

Warranty & Service

231

Owner's Manual and Troubleshooting
You should read the owner’s manual thoroughly before operating this product. In theunlikely event that you should encounter difficulty operating this product, the owner’s
manual should be consulted before contacting the Princeton Instruments technical support
staff or authorized service representative for assistance. If you have consulted the owner's
manual and the problem still persists, please contact the Princeton Instruments technicalsupport staff or our authorized service representative. See Item 12 in the following sectionof this warranty ("Your Responsibility") for more information.

Your Responsibility
The above Limited Warranties are subject to the following terms and conditions:
1. You must retain your bill of sale (invoice) and present it upon request for service
and repairs or provide other proof of purchase satisfactory to Princeton
Instruments.
2. You must notify the Princeton Instruments factory service center within (30)days after you have taken delivery of a product or part that you believe to be
defective. With the exception of customers who claim a "technical issue" with theoperation of the product or part, all invoices must be paid in full in accordancewith the terms of sale. Failure to pay invoices when due may result in theinterruption and/or cancellation of your one (1) year limited warranty and/or any
other warranty, expressed or implied.
3. All warranty service must be made by the Princeton Instruments factory or, at our
option, an authorized service center.
4. Before products or parts can be returned for service you must contact the
Princeton Instruments factory and receive a return authorization number (RMA).
Products or parts returned for service without a return authorization evidenced by
an RMA will be sent back freight collect.
5. These warranties are effective only if purchased from the Princeton Instruments
factory or one of our authorized manufacturer's representatives or distributors.
6. Unless specified in the original purchase agreement, Princeton Instruments is not
responsible for installation, setup, or disassembly at the customer’s location.
7. Warranties extend only to defects in materials or workmanship as limited above
and do not extend to any product or part which has:
been lost or discarded by you;
been damaged as a result of misuse, improper installation, faulty or
inadequate maintenance or failure to follow instructions furnished by us;
had serial numbers removed, altered, defaced, or rendered illegible;
been subjected to improper or unauthorized repair; orbeen damaged due to fire, flood, radiation, or other "acts of God" or othercontingencies beyond the control of Princeton Instruments.
8. After the warranty period has expired, you may contact the Princeton Instruments
factory or a Princeton Instruments-authorized representative for repair
information and/or extended warranty plans.
9. Physically damaged units or units that have been modified are not acceptable forrepair in or out of warranty and will be returned as received.

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10. All warranties implied by state law or non-U.S. laws, including the implied
warranties of merchantability and fitness for a particular purpose, are expressly
limited to the duration of the limited warranties set forth above. With the exceptionof any warranties implied by state law or non-U.S. laws, as hereby limited, theforgoing warranty is exclusive and in lieu of all other warranties, guarantees,
agreements, and similar obligations of manufacturer or seller with respect to therepair or replacement of any parts. In no event shall Princeton Instruments' liability
exceed the cost of the repair or replacement of the defective product or part.
11. This limited warranty gives you specific legal rights and you may also have otherrights that may vary from state to state and from country to country. Some states
and countries do not allow limitations on how long an implied warranty lasts,
when an action may be brought, or the exclusion or limitation of incidental orconsequential damages, so the above provisions may not apply to you.
12. When contacting us for technical support or service assistance, please refer to the
Princeton Instruments factory of purchase, contact your authorized Princeton
Instruments representative or reseller, or visit our technical support page atwww.princetoninstruments.com.

Contact Information
Roper Scientific's manufacturing facility for this product is located at the following
address:
Princeton Instruments
3660 Quakerbridge Road
Trenton, NJ 08619 (USA)
Tel: 800-874-9789 / 609-587-9797
Fax: 609-587-1970
Customer Support E-mail: techsupport@princetoninstruments.com
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Index#-A
500 ps gating option ................................................ 91
64-pin DIN connector .................................... 156, 180
A/D converters ....................................................... 187
dual ...................................................................... 67
standard ............................................................. 187
AC power requirements ........................................... 35
Accessories, alignment of ...................................... 205
Acton adapter instructions ............................. 206, 207
Adapter instructions
Acton ......................................................... 206, 207
Chromex 250 IS ................................................ 208
ISA HR 320 ....................................................... 209
ISA HR 640 ....................................................... 210
SPEX 270M ...................................................... 211
SPEX 500M ...................................................... 212
SPEX TripleMate .............................................. 213
Alarmcontroller ................................. xv, 21, 82, 108, 141disabling of photocathode and MCP power . xv, 21,
82, 108
protection circuit ................................................. 33
Alignment
Safe Mode operation ........................................... 70
Analog channels ...................................................... 67
Analog/Control module ......................................... 156
Anticipator ............................................................... 87
Application, typical .......................................... 89, 118
Aux Out, PTG connector................................ 157, 159

B
BackgroundDC level .............................................................. 55
Background baseline level ..................................... 141
Background subtraction ......................................... 147
Back-plane ............................................................. 156
Baseline level......................................................... 141
Baseline signal ......................................................... 55
excessive humidity ...................................... 55, 165
ST-133 zero adjustment..................................... 157
sudden change in ......................................... 55, 165
Binningcomputer memory burden ................................... 64
hardware .............................................................. 64
full frame ........................................................ 65
interline CCD .................................................. 66
restrictions due to well capacity ........................ 65
readout time ......................................................... 64

Binning (cont.)
resolution loss ...................................................... 64
softwareeffect on S/N ratio ........................................... 66
high light level measurements ........................ 66
shot-noise limited measurements .................... 66
Blooming ................................................................. 59
Bottom clamps, table of ......................................... 144
Bracket pulsing
Anticipator ........................................................... 87
effect on coincidence timing ....................... 86, 116
impact on coincidence timing ....................... 87, 117
Main .................................................................... 87
Main+Burst ......................................................... 87
need for ........................................................ 85, 115
Pre-Trigger .......................................................... 87

C
Cables
Detector-Controller ........................................... 162
fiber optic ........................................................... 162
Gen II ................................................................ 163
Gen III ............................................................... 163
PCI interface....................................................... 162
TAXI.................................................................. 162
USB 2.0 ............................................................. 162
Calibration
spectroscopy
suitable light sources..................................... 204
Cameramounting considerations
orientation constraints ............................. 37, 201
use of mounting bracket for security ...... 37, 201
Camera Detection wizard ........................................ 45
Camera state dialog box ........................................ 193
Cautions
coolant fittings ..................................................... 44
coolant pH ........................................................... 44
coolant temperature ............................................. 44
DMA and Interrupt ............................................ 175
excessive humidity in CCD chamber .......... 55, 165
need for nitrogen flushing even if not cooling .. 215
need to contact factory in case of sporadic orcontinuous unwarranted alarms..................... 141
sporadic or continuous unwarranted alarms . xv, 21,
82, 108
CC-100 .................................................................. 154

233

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CCD arraybinning................................................................. 64
blooming ............................................................. 59
maximum on-chip integration ............................. 59
readout of ............................................................. 60
readout theory...................................................... 60
shift register ......................................................... 60
shutter function ..................................................... 59
signal-to-noise ratio vs on chip integration time . 59
theory of operation .............................................. 58
well capacity ........................................................ 59
Chromex 250 IS adapter instructions..................... 208
Circulator, closed ................................................... 154
Clean cycles .............................................................. 55
Cleaning ................................................................... 22
Cleaning optical surfaces ......................................... 23
C-mount ................................................................. 146
assembly ............................................................ 146
support recommendations .................................. 146
C-mount lens, installation and removal ................. 200
Coincidence, how to measure ................................ 136
Composite video output ......................................... 157
Connectors
PI-MAX, Monitor.............................................. 154
PI-MAX, Power/Signal ..................................... 153
PI-MAX, Timing Gen ....................................... 153
PI-MAX2, Power .............................................. 153
PI-MAX2, Signal .............................................. 153
PTG, Aux. Trig. Out .................................. 157, 159
PTG, Ext. Trig In....................................... 158, 160
PTG, Pre. Trig In ....................................... 158, 160
PTG, T0 ..................................................... 158, 160
PTG, Timing Gen ...................................... 157, 159
ST-133, AUX Output ................................ 157, 159
ST-133, Camera Power ..................................... 159
ST-133, Camera Signal ..................................... 159
ST-133, Detector ....................................... 157, 159
ST-133, External Sync .............................. 157, 159
ST-133, NOTREADY ............................... 157, 159
ST-133, NOTSCAN .................................. 157, 159
ST-133, Serial COM ................................. 158, 159
ST-133, TTL In/Out .................................. 157, 159
ST-133, USB 2.0 ............................................... 158
ST-133, Video Output ....................................... 157
Contact information ............................................... 232
Continuous cleans .................................................... 56
Controller modules ................................................ 156
Coolant
circulator installation ........................................... 44
flow rate .............................................................. 44
fluid pressure, maximum ..................................... 44
mixture ................................................................. 44
pH ........................................................................ 44
temperature .......................................................... 44
C-type lens mount .................................................. 200

Version 5.G

Customer support ................................................... 232

DDanger Notices
high voltage ......................................................... 33
Dark charge ..................................................... 68, 147
dynamic range ..................................................... 59
Dark charge pattern ....................................... 140, 141
Dark current ........................................................... 219
Declaration of Conformity
PI-MAX with ST-133........................................ 227
PI-MAX with ST-133 and PTG ........................ 226
PI-MAX2 with 16-Bit 5 MHz ST-133 .............. 228
Depth of field ......................................................... 140
Detector connector (ST-133) ......................... 157, 159
Detectors, rotation of ............................................. 205
DG535, software control of ................................... 193
Diagnostic Instruments Bottom Clamp ................... 144
Diagnostic Instruments Relay Lens ........................ 144
DIF
dual trigger mode ............................................... 131
requirements ...................................................... 129
single trigger mode ............................................ 130
timing modes ..................................................... 130
Digitization .............................................................. 67
DMA buffer ........................................................... 178
Double Image Feature .................................... See DIF
Dual A/D converters ................................................ 67
Dual Image Feature ........................................ See DIF
Dual trigger mode................................................... 131
Dynamic range ......................................................... 59

E-F
EBI ............................................................. 59, 68, 147
Equivalent Brightness Intensity (EBI) ........................ 59
Ethylene glycol ......................................................... 44
Excess Rep Rate indicator ..................................... 154
Excessive humidity .................................. 55, 165, 166
Experiment types ..................................................... 92
Exposure and Readout............................................... 53
Ext Trig In, PTG connector ............................ 158, 160
External Sync
DG535 D output ................................................ 109
input pulse ......................................................... 109
timing ................................................................ 109
External synchronization ................ See External Sync
External Trigger
gate delay ............................................................ 98
Fan ................................................... 35, 155, 158, 159
Fast Gating Experiment ................................... 83, 113
Fast mode
data acquisition .................................................... 69
flowchart ............................................................. 71
image update lag.................................................. 69
Fiber optic cable (PCI optional) ............................... 162
Flow rate, coolant .................................................... 44

Index
Fluid pressure, flow rate .......................................... 44
Fluorescence experiment, typical...................... 89, 118
Fluorescence measurements .................................. 147
Focusing
adjusting camera parfocality ............................. 147
C-mount or F-mount lenses ............................... 201
spectrograph-detector ........................................ 204
Full Frame CCD
hardware binning ................................................. 65
Full frame readout ................................................... 60
Fuse
replacement ....................................................... 168
requirements ........................................................ 35

G-H
Gate Width and Delay optimization ...................... 138
Gated operation
500 ps option ....................................................... 91
advantages of ............................................... 81, 107
extended-exposure pulsing .......................... 83, 109
Gen II cabling requirements .................................. 163
Gen III cabling requirements ................................. 163
Grounding and safety (ST-133) ............................... 21
Hamamatsu PL0-01Picosecond Light Source . 83, 113
Hardware binning .................................................... 64
Hardware Setup wizard ........................................... 46
Heat removal block ................................................ 155
High level radiation, definition of ......................... 135
Hose connections ..................................................... 44
Humidity requirement ............................................ 163

I-J
I/O Address conflicts ............................................. 175
IEC Publication 348................................................. 21
IEEE-488 GPIB link .............................................. 197
image intensifier gain .............................................. 68
Inhibiting gating during readout ............................ 139
Installation ............................................................... 33
coolant circulator ................................................. 44
hose connections ................................................. 44
PCI card driver .................................................... 39
tubing................................................................... 44
USB 2.0 driver..................................................... 41
Intensifier
EBI....................................................................... 59
MCP .................................................................... 59
Intensifier alarmdisabling of photocathode and MCP power ...... 141
reason for ........................................................... 141
required response............................................... 141
Intensifier gain
effect on dark charge ......................................... 147
Interface card
PCI
High Speed PCI .............................................. 39
PCI(Timer) ...................................................... 39

235
Interface card (cont.)
USB 2.0 ............................................................... 40
Interface Control module ....................................... 156
Interline CCD
DIF capability.................................................... 129
hardware binning ................................................. 66
non-overlapped operation .................................... 62
overlapped operation ........................................... 61
readout rate .......................................................... 63
Internal pulser ........................................................ 188
Interrupt conflicts .................................................. 175
IR blockers............................................................. 148
IR sensitivity .......................................................... 148
ISA HR 320 adapter instructions ........................... 209
ISA HR 640 adapter instructions ........................... 210
ISA serial card
I/O address, DMA channel, and interrupt level . 175

K-L
Kinetics .................................................................. 123
ICCD ................................................................. 121
operation ............................................................ 121
Koehler illumination .............................................. 146
Lasersfree-running ....................................................... 138
jitter ................................................................... 139
overview ............................................................ 138
triggered ............................................................ 139
Lens
depth of field ..................................................... 140
focusing ............................................................. 201
installation and removal .................................... 200
lens coupling effects ............................................ 20
mounting ...................................................... 37, 200
performance considerations ............................... 139
resolution ........................................................... 140
throughput ......................................................... 140
Light throughput in microscopy ............................ 143
Line voltage selection
procedure ........................................................... 168
selector drum ....................................................... 36

M
Main tab page, overview........................................ 194
Main+Burst .............................................................. 87
Maintenance ............................................................ 22
MCP................................................................... 17, 59
MCP bracket pulsing ......................................... 85, 115
MCP On/Off switch ............................................... 153
Microchannel Plate (MCP) ...................................... 59
Microscope
adapters ............................................................... 37
mounting ............................................................ 143
C-mount ........................................................ 146
F-mount ......................................................... 144

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Microscopy
focusing ............................................................. 147
IR blockers ........................................................ 148
light throughput ................................................. 143
parfocality ......................................................... 147
Moduleinstallation ......................................................... 180
removal .............................................................. 180
Monitor connector ................................................. 154
Mounting
microscope ......................................................... 143
C-mount ........................................................ 146
F-mount ......................................................... 144
spectrograph ........................................................ 37

N-O
Nitrogenconnecting source to camera ............................. 216
continued flushing after shutting down experiment...................................................................... 216
flushing with nitrogen or dry air ........................ 215
Non-Overlapped operation, example ....................... 62
NOTSCAN signal .......................................... 157, 159
NVRAM calibration ................................................ 98
Optical-fiber adapter and cable ................................ 51
Outline drawings
PI-MAX/PI-MAX2 with C-mount adapter........ 189
PI-MAX/PI-MAX2 with F-mount adapter ........ 189
PI-MAX/PI-MAX2 with spectroscopy adapter . 190
ST-133A ............................................................ 190
ST-133B ............................................................ 191
Overexposure protection........................................ 135
Overlapped operation
example ............................................................... 61

P-Q
Parfocality.............................................................. 147
PCI
cable .................................................................. 162
card installation ................................................... 39
diagnostics software .......................................... 177
driver installation................................................. 39
fiber optic adapters.............................................. 162
non-conforming peripheral cards ...................... 177
TAXI protocol ................................................... 161
Peltier type cooler .................................................... 17
PI-MAX
pulsed operation ................................................ 161
rear panel features ............................................. 153
software control of ............................................ 193
Timing Gen connector ............................... 157, 159
PI-MAX2
DIF operation .................................................... 129
rear panel features ............................................. 153
Plug-in modules, installation and removal ................ 180
Power connector, PI-MAX2 .................................. 153

Version 5.GPower cord ............................................................... 35
Power module (ST-133) ................................ 158, 160
Power requirements ................................................. 35
Power switch and indicator .................................... 156
Power/Signal connector, PI-MAX ......................... 153
Pre Trig In, PTG connector ........................... 158, 160
Pre-Trigger .............................................................. 87
Princeton Instruments USB 2 driver installation ..... 41
Procedures
adapter installation............................................ 204
line voltage selection and line fuse .................... 168
plug-in module installation/removal .................. 180
Programmable Interface connector .......................... 149
Programmable TTL interface
connector ................................................... 157, 159
pinout levels ....................................................... 149
PTG
Aux Out ..................................................... 157, 159
description ......................................................... 161
Ext Trig In .................................................. 158, 160
Pre Trig In ................................................. 158, 160
T0 .............................................................. 158, 160
Timing Gen ............................................... 157, 159
Trig indicator ............................................. 158, 160
Pulserinhibiting during readout ................................... 139
internal............................................................... 188
PVCAM.INI .................................................... 45, 167

R
Readout
binning................................................................. 64
full frame ............................................................. 60
inhibiting gating during readout ........................ 139
interline ............................................................... 61
subsection of array .................................... 61, 63, 64
Readout pattern, subtractable................................. 141
Readout rate
control of ............................................................. 67
precision vs speed tradeoff .................................. 67
Readout times (full frame) for several CCD types
table of ................................................................. 64
Relay Lens ............................................................. 144
Requirements
humidity ............................................................ 163
power ................................................................... 35
ventilation ............................................................ 35
Resolution, loss of with binning .............................. 64
Restore last settings ............................................... 193
RSConfig.exe ................................................... 45, 167

S
S/N ratio............................................................. 59, 66
Safe mode .............................................................. 193
as used for setting up ........................................... 70
fast image update ................................................. 70

Index
Safe mode (cont.)
flowchart ............................................................. 71
missed events....................................................... 70
Saturation ................................................................. 59
Sequential Control function ............................. 84, 114
Serial COM connector, ST-133 ..................... 158, 159
Setup ........................................................................ 33
Shift register ............................................................ 60
Shuttercompensation time ............................................. 187
shutter setting selector (ST-133) ............... 157, 159
ST-133 connector ....................................... 157, 159
SHUTTER signal ........................................... 157, 159
Signal and Gate coincidence requirements ............ 135
Signal connector, PI-MAX2 .................................. 153
Signal delay ........................................................... 135
adjustment of to achieve coincidence ................ 137
Signal-to-noise ratio
on-chip integration .............................................. 59
Single trigger mode ............................................... 130
Slide latch operation .............................................. 181
Software binning...................................................... 66
Software control .................................................... 193
Specifications
computer ............................................................ 185
general ............................................................... 183
internal pulser .................................................... 188
operating environment ....................................... 186
ST-133 ............................................................... 186
Spectrographs
Acton ................................................................. 204
adapter instructions ........................................... 204
adapters ............................................................... 37
Chromex 250IS ................................................. 204
focusing and alignment ..................................... 204
ISA HR320 ........................................................ 204
ISA HR640 ........................................................ 204
SPEX 270M adapter instructions ........................... 211
SPEX 500M adapter instructions ........................... 212
SPEX TripleMate adapter instructions .................. 213
ST-133 Controller
description of ..................................................... 155
fuse/voltage label....................................... 158, 160
grounding and safety ........................................... 21
power module ............................................ 158, 160
power requirements ............................................. 35
zero adjustment ................................................. 157

T
T0, PTG connector ........................................ 158, 160
TAXI .............................................................. See PCI
Technical support .................................................. 232
Temperature control
loss of lock ........................................................ 141
problems............................................................. 182
thermal protection switch .................................. 141

237
Temperature control (cont.)
time to lock................................................... 57, 155
time to stabilize ................................................. 141
water coolingchilled water constraint ................................... 44pressure and flow rate ..................................... 44
required connections ....................................... 44
Tygon tubing ................................................... 44
Temperature Lock LED (ST-133) ................. 157, 159
Theory of operation .................................................. 19
Thermal protection switch ..................................... 141
Thomson 512 × 512 chippreamplifier selector switch .............................. 142
Time budget ........................................................... 135
Timing coincidence, how to achieve ..................... 135
Timing Gen connector
PI-MAX............................................................. 153
PTG ........................................................... 157, 159
Timing modes .................................................. 74, 109
Timing options in Shutter Mode operation .............. 73
Tips and Tricks ...................................................... 135
Trig indicator
PI-MAX............................................................. 154
PTG ........................................................... 158, 160
TTL In/Out
hardware interface ............................................. 151
pin assignments .................................................. 149
ST-133 connector ...................................... 157, 159
Tubing connections.................................................. 44

U-V
Unpacking and initial inspection ............................. 33
Upgrade Device Driver wizard ................................ 41
USB 2.0
cable .................................................................. 162
connector ........................................................... 158
data overrun ....................................................... 170
installation ........................................................... 41
interface card ..................................................... 161
Ventilation fan ....................................................... 155
Ventilation requirements ......................................... 35
Vignetting ................................................................ 20

W-Z
Warnings
Controller/Detector cable .................................. 156
coolant pH ........................................................... 44
damage from operating camera that has lost its
nitrogen backfill ...................................... 23, 216
destruction of intensifier caused by excess light135
F-mount cameras and nose-up operation ..... 37, 201
intensifier destruction from flushing with noble gas 215
module installation/removal under power ......... 156
need for cooling water to be at ambient temperature. 58
opening the ST-133 power module ................... 168
operation without evacuation or backfill ............. 22

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PI-MAX/PI-MAX2 System Manual

Warnings (cont.)
overtightening the ST-133 module screws ........ 180
protective grounding ........................................... 21
replacement power cord ...................................... 21
ST-133 fuse type ............................................... 168
ST-133 module installation/removal under power .. 179
Timing Gen disconnect in Shutter mode ..... 81, 107
touching the CCD array ....................................... 22
use of unspecified "dry" gas .............................. 216
window removal .................................................. 22
Xenon or Hg arc lamp ....................................... 146
Warranties
image intensifier detector .................................. 230
one year ............................................................. 229
one year on refurbished/discontinued products . 229
owner's manual and troubleshooting................... 231
sealed chamber .................................................. 230

Version 5.G

Warranties (cont.)
software ............................................................. 230
vacuum integrity ................................................ 230
XP vacuum chamber ......................................... 229
x-ray detector..................................................... 230
your responsibility ............................................. 231
Water ports ............................................................ 154
Website .................................................................. 232
Well capacity
blooming ............................................................. 59
dark charge .......................................................... 59
restrictions on hardware binning ............................ 65
saturation ............................................................. 59
WizardCamera Detection ................................................ 45
Hardware Setup ................................................... 46
Upgrade Device Driver ....................................... 41