4411-0129
Version 1.D
September 21, 2015

Copyright 2009-2015

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.
Pentium is a registered trademark of Intel Corporation.
PVCAM is a registered trademark of Photometrics, Ltd. Corporation
Scientific Imaging ToolKit and SITK are trademarks of R Cubed Software Consultants, LLC.
IntelliCal, PICam, SuperSYNCHRO, and SyncMASTER are trademarks and LightField and PI-MAX is a
registered trademark of Roper Scientific, Inc.
Windows and Windows Vista are registered trademarks of Microsoft Corporation in the United States
and/or other countries.
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! .......................................................................................................... xiii
Chapter 1 Introduction ...................................................................................... 15
PI-MAX3 System Components ........................................................................................ 15
Camera ....................................................................................................................... 15
Cable........................................................................................................................... 16
Computer Interface:.................................................................................................... 16
Tubing ........................................................................................................................ 16
Manuals ...................................................................................................................... 16
Optional Application Software ................................................................................... 16
Summary of PI-MAX3 Data Acquisition ......................................................................... 16
Safety Information ............................................................................................................ 18
Safety Related Symbols Used in This Manual ........................................................... 18
Grounding and Safety................................................................................................. 18
Intensifier Modes and Safety ...................................................................................... 18
Audible Alarm ............................................................................................................ 19High Intensity Light Damage ..................................................................................... 19
Precautions ........................................................................................................................ 19
Cleaning and Maintenance................................................................................................ 20
Cleaning the Camera .................................................................................................. 20
Cleaning Optical Surfaces – UnigenTMII Coating ...................................................... 20
Cleaning Optical Surfaces – Protective Window ....................................................... 20
Flushing and Refilling the CCD Chamber ................................................................. 20
Repairs .............................................................................................................................. 21
About this Manual ............................................................................................................ 21
Manual Organization .................................................................................................. 21

Chapter 2 Installation Overview ....................................................................... 23
Chapter 3 System Setup ................................................................................... 25
Introduction....................................................................................................................... 25
Dangers and Warnings ...................................................................................................... 25
Unpacking the System ...................................................................................................... 25
Checking the Equipment and Parts Inventory................................................................... 25
System Requirements ....................................................................................................... 26
Environmental ............................................................................................................ 26
Ventilation .................................................................................................................. 26
Power.......................................................................................................................... 27
Host Computer ........................................................................................................... 27
Mounting the PI-MAX3.................................................................................................... 28
Imaging Applications ................................................................................................. 28
Spectroscopy Applications ......................................................................................... 28
Software Installation ......................................................................................................... 29
WinX .......................................................................................................................... 29
LightField ................................................................................................................... 29
iii

iv

PI-MAX®3 System Manual

Version 1.D

Making the Camera-Circulator Connections .................................................................... 30
Making the Camera to Dry Nitrogen Source Connections ............................................... 31
Entering the Default Camera System Parameters ............................................................. 31
WinX (Versions 2.5.25.X or higher) .......................................................................... 31
LightField ................................................................................................................... 32

Chapter 4 First Light ......................................................................................... 33
Introduction....................................................................................................................... 33
Required Equipment and Cables ....................................................................................... 33
Cable Connections ............................................................................................................ 33
Before Turning on the System .......................................................................................... 34
Turning on the System ...................................................................................................... 34
WinX First Light Instructions ........................................................................................... 34
Introduction ................................................................................................................ 34
Assumptions ............................................................................................................... 34
Getting Started............................................................................................................ 34
Configuring the Software ........................................................................................... 35
Initial Data Acquisition .............................................................................................. 37
Focusing ..................................................................................................................... 38
LightField First Light Instructions .................................................................................... 38
Introduction ................................................................................................................ 38
Assumptions ............................................................................................................... 38
Getting Started............................................................................................................ 38
Setting the Parameters ................................................................................................ 39
Acquiring Data ........................................................................................................... 40
Focusing ..................................................................................................................... 42
Final Comments ................................................................................................................ 42

Chapter 5 General Operation Factors ............................................................. 43
Introduction....................................................................................................................... 43
Data Acquisition Sequence ............................................................................................... 43
WinX System On/Off Sequences...................................................................................... 44
Pre-Exposure Removal of Accumulated Charge .............................................................. 44
Introduction ................................................................................................................ 44
Dark Charge ............................................................................................................... 44
Cleaning ..................................................................................................................... 45
Phosphor Decay Delay...................................................................................................... 47
Temperature Control ......................................................................................................... 47
Cooling Method.......................................................................................................... 47
Setting the Temperature ............................................................................................. 48
Exposure ........................................................................................................................... 49
Introduction ................................................................................................................ 49
Exposure with an Image Intensifier............................................................................ 49
Saturation ................................................................................................................... 49
Background Subtraction ................................................................................................... 50
Readout of the Array......................................................................................................... 50
Interline CCD Readout ............................................................................................... 51
Full Frame CCD Readout ........................................................................................... 54
Binned Readout (Hardware Binning) ......................................................................... 56
Software Binning .............................................................................................................. 62

Table of Contentsv

Controller Gain {Analog Gain} ........................................................................................ 62
Digitization ....................................................................................................................... 63
Logic Out Control ............................................................................................................. 63
WinX Experiment Setup ................................................................................................... 64
Main tab...................................................................................................................... 64
Timing tab .................................................................................................................. 65
LightField Experiment Setup ............................................................................................ 68
Introduction ................................................................................................................ 68
Common Acquisition Settings expander .................................................................... 68
Region of Interest expander ....................................................................................... 69
Trigger expander ........................................................................................................ 69
SuperSYNCHRO Timing expander ........................................................................... 70

Chapter 6 WinX and Gated Operation ............................................................. 71
Introduction....................................................................................................................... 71
Precautionary Measures .................................................................................................... 72
Intensifier Modes and Safety ...................................................................................... 72
Alarm.......................................................................................................................... 72
Timing Mode .................................................................................................................... 73
MCP Bracket Pulsing........................................................................................................ 73
Introduction ................................................................................................................ 73
Bracket Pulsing in LIF Measurements ....................................................................... 74
Bracket Pulsing in Nanosecond Pump Probe Experiments ........................................ 74
Limitations of Bracket Pulse Gating .......................................................................... 75
Impact of Bracket Pulsing on Delay........................................................................... 75
Setup ........................................................................................................................... 76
Additional Experiments .................................................................................................... 77
Introduction ................................................................................................................ 77
Procedure for Setting up and Performing a Swept Gate Experiment (Fixed
Width, Variable Delay) ........................................................................................ 78
Procedure for Setting up and Performing a Single Shot Experiment ......................... 86
Procedure for Setting up and Performing a Swept Gate Experiment (Variable
Width, Variable Delay) ........................................................................................ 89
Procedure for Setting up and Performing a Static Gate Experiment (Fixed
Width, Fixed Delay) ............................................................................................ 90

Chapter 7 LightField and Gated Operation ..................................................... 91
Introduction....................................................................................................................... 91
Precautionary Measures .................................................................................................... 92
Intensifier Modes and Safety ...................................................................................... 92
Alarm.......................................................................................................................... 92
Timing Mode .................................................................................................................... 93
MCP Bracket Pulsing........................................................................................................ 93
Introduction ................................................................................................................ 93
Bracket Pulsing in LIF Measurements ....................................................................... 94
Bracket Pulsing in Nanosecond Pump Probe Experiments ........................................ 94
Limitations of Bracket Pulse Gating .......................................................................... 95
Impact of Bracket Pulsing on Delay........................................................................... 95
Setup ........................................................................................................................... 96
Additional Experiments .................................................................................................... 96

vi

PI-MAX®3 System Manual

Version 1.D

Introduction ................................................................................................................ 96
Procedure for Setting up and Performing a Swept Gate Experiment (Fixed
Width, Variable Delay) ........................................................................................ 97
Procedure for Setting up and Performing a Single Shot Experiment ....................... 106
Procedure for Setting up and Performing a Swept Gate Experiment (Variable
Width, Variable Delay) ...................................................................................... 110
Procedure for Setting up and Performing a Static Gate Experiment (Fixed
Width, Fixed Delay) .......................................................................................... 110

Chapter 8 Timing Generator Pulses and Sequences ................................... 111
Pulse Set.......................................................................................................................... 111
Description ............................................................................................................... 111
Supported Timing Generator Trigger Modes: .......................................................... 111
Single Sequence .............................................................................................................. 112
Supported Timing Generator Trigger Modes: .......................................................... 112
Time Stamping ................................................................................................................ 113

Chapter 9 WinX and Dual Image Feature (DIF) ............................................. 115
Introduction..................................................................................................................... 115
Requirements .................................................................................................................. 115
Interline CCD Operation ................................................................................................. 115
Timing Modes ................................................................................................................. 116
Setting Up a Single Trigger DIF Experiment ................................................................. 116
Hardware .................................................................................................................. 116
Software ................................................................................................................... 116
Operation .................................................................................................................. 116
Setting Up a Dual Trigger DIF Experiment .................................................................... 119
Hardware .................................................................................................................. 119
Software ................................................................................................................... 119
Operation .................................................................................................................. 119
Tips and Tricks ............................................................................................................... 122

Chapter 10 LightField and Dual Image Feature (DIF) ................................... 123
Introduction..................................................................................................................... 123
Requirements .................................................................................................................. 123
Interline CCD Operation ................................................................................................. 124
Trigger Setup .................................................................................................................. 124
Introduction .............................................................................................................. 124
Trigger Response...................................................................................................... 124
Trigger Source .......................................................................................................... 125
Setting Up a Single Trigger DIF Experiment ................................................................. 126
Hardware Setup ........................................................................................................ 126
Software Setup and Operation .................................................................................. 126
Setting Up a Dual Trigger DIF Experiment .................................................................... 128
Hardware Setup ........................................................................................................ 128
Software Setup and Operation .................................................................................. 128
Tips and Tricks ............................................................................................................... 130

Chapter 11 MCP Gating Option ...................................................................... 131
Introduction..................................................................................................................... 131

Table of Contentsvii

Setup and Operation........................................................................................................ 131
Gain Variation................................................................................................................. 131
Fluorescence Experiment ................................................................................................ 132
Cabling for MCP Gated Operation ................................................................................. 132

Chapter 12 Picosecond Option ...................................................................... 135
Introduction..................................................................................................................... 135
Activating Picosecond Operation ................................................................................... 135
Gain and Gate Width ...................................................................................................... 135
MONITOR Operation ..................................................................................................... 135
Repetition Rate Issues ..................................................................................................... 136
Timing............................................................................................................................. 136
Methods for Finding a Short Optical Pulse..................................................................... 136

Chapter 13 General Tips and Tricks .............................................................. 139
Introduction..................................................................................................................... 139
Overexposure Protection................................................................................................. 139
Signal Delay.................................................................................................................... 139
Introduction .............................................................................................................. 139
Time Budgets ........................................................................................................... 139
Measuring Coincidence ............................................................................................ 140
Adjusting the Signal Delay....................................................................................... 141
Optimizing the Gate Width and Delay ..................................................................... 141
Lasers .............................................................................................................................. 142
Free Running Lasers................................................................................................. 142
Triggered Lasers ....................................................................................................... 142
Jitter .......................................................................................................................... 143
Inhibiting the Pulser during Readout .............................................................................. 143
Lens Performance ........................................................................................................... 143
Throughput ............................................................................................................... 143
Depth of Field........................................................................................................... 143
Baseline Signal ............................................................................................................... 144
Temperature Lock ........................................................................................................... 144
Intensifier Alarm ............................................................................................................. 144

Chapter 14 System Component Descriptions .............................................. 146
Introduction..................................................................................................................... 146
PI-MAX3 Camera ........................................................................................................... 146
Mount Adapters ........................................................................................................ 146
Switches, Connectors and Indicators........................................................................ 146
Interface Card ................................................................................................................. 148
Extender Bracket Kit ...................................................................................................... 148
CoolCUBEII Coolant Circulator (Option) ....................................................................... 148
Spectrograph (Option) .................................................................................................... 148
Cables ............................................................................................................................. 148
Tubing ............................................................................................................................. 149
Application Software ...................................................................................................... 149
User Manuals .................................................................................................................. 150

viii

PI-MAX®3 System Manual

Version 1.D

Chapter 15 Troubleshooting .......................................................................... 152
Introduction..................................................................................................................... 152
Alarm Sounds Repetitively ............................................................................................. 153
Alarm Sounds Sporadically ............................................................................................ 153
Baseline Signal Suddenly Changes by > 1000 ADU ...................................................... 153
Camera Is Not Responding ............................................................................................. 153
Camera Stops Working ................................................................................................... 154
Cooling Troubleshooting ................................................................................................ 154
Temperature Lock Cannot be Achieved or Maintained. .......................................... 154
Gradual Deterioration of Cooling Capability ........................................................... 155
Data Loss or Serial Violation .......................................................................................... 155
Error Occurs at Computer Powerup ................................................................................ 155
Ethernet Network is not accessible ................................................................................. 155
For WinX: ................................................................................................................ 155
For LightField: ......................................................................................................... 156
Excessive Readout Noise ................................................................................................ 157

Appendix A Specifications ............................................................................. 158
PI-MAX3 ........................................................................................................................ 158
Internal Pulser ................................................................................................................. 164
Intensifier Quantum Efficiency....................................................................................... 164
CoolCUBEII Circulator ................................................................................................... 165
Computer ........................................................................................................................ 165
Operating Environment................................................................................................... 166

Appendix B Outline Drawings ........................................................................ 168
PI-MAX3 ........................................................................................................................ 168
PI-MAX3 Power Supply ................................................................................................. 171
CoolCUBEII Circulator ................................................................................................... 172

Appendix C Cross-Referencing of WinX and LightField Terms .................... 174
WinX-to-LightField ........................................................................................................ 174
LightField-to-WinX ........................................................................................................ 176

Appendix D Extender Bracket Kit .................................................................. 178
Appendix E Mounting and Focusing C-Mount and F-Mount Lenses ........ 180
Mounting the Lens .......................................................................................................... 180
Mounting Orientation ..................................................................................................... 180
Focusing .......................................................................................................................... 181

Appendix F C-, F-, and Spectroscopy-Mount Adapters ................................. 182
Accessory Kits ................................................................................................................ 182
PI-MAX3 18 mm Tube ............................................................................................ 182
PI-MAX3 25 mm Tube ............................................................................................ 182
Adapter Kits .................................................................................................................... 182
PI-MAX3 to Acton Spectrograph Quick Start Guides.................................................... 183
Standard C-, F-, and Spectroscopy-Mount Adapters ...................................................... 183
Spectroscopy-Mount for NVUV Cameras ...................................................................... 183

Table of Contentsix

Optical Distance from Mounting Face to Image Plane ................................................... 184

Appendix G Spectrograph Adapters ............................................................. 186
Introduction..................................................................................................................... 186
Spectrograph-Detector Focusing .................................................................................... 186
Acton Series Spectrograph ....................................................................................... 186
IsoPlane SCT-320 Spectrograph .............................................................................. 188
Mounting a PI-MAX3 (3.60 3-hole Slotted Flange) to an Acton Series
Spectrograph............................................................................................................. 190
Tools ......................................................................................................................... 190
Procedure.................................................................................................................. 190
Acton (C-Mount Adapter)............................................................................................... 192
Mounting a PI-MAX3 to an IsoPlane SCT-320 ............................................................. 193

Appendix H Glossary ...................................................................................... 194
Declaration of Conformity .............................................................................. 200
Warranty & Service ......................................................................................... 202
Limited Warranty ............................................................................................................ 202
Basic Limited One (1) Year Warranty ..................................................................... 202
Limited One (1) Year Warranty on Refurbished or Discontinued Products ............ 202
XP Vacuum Chamber Limited Lifetime Warranty .................................................. 202
Sealed Chamber Integrity Limited 12 Month Warranty........................................... 202
Vacuum Integrity Limited 12 Month Warranty ....................................................... 203
Image Intensifier Detector Limited One Year Warranty .......................................... 203
X-Ray Detector Limited One Year Warranty .......................................................... 203
Software Limited Warranty ...................................................................................... 203
Owner's Manual and Troubleshooting ..................................................................... 203
Your Responsibility.................................................................................................. 204
Contact Information ........................................................................................................ 205

Index ................................................................................................................. 206

FiguresFigure 1. Typical PI-MAX3 System Components ........................................................... 15
Figure 2. Major Components of the Intensifier-CCD ...................................................... 16
Figure 3. PI-MAX3 System Diagram .............................................................................. 24
Figure 4. WinView Installation: Select Installation Type dialog.................................... 29
Figure 5. LightField Installation Wizard dialog............................................................... 30
Figure 6. Camera Detection Wizard - Welcome dialog ................................................... 31
Figure 7. Available Devices Area .................................................................................... 39
Figure 8. Experiment Devices Area ................................................................................. 40
Figure 9. View Area......................................................................................................... 41
Figure 10. View Area Displaying an Image .................................................................... 41
Figure 11. Block Diagram of Signal Path in Standard PI-MAX3 System ....................... 43
Figure 12. Clean Cycles in Internal Trigger Mode of Operation ..................................... 45
Figure 13. WinX: Phosphor Decay Delay ....................................................................... 47

x

PI-MAX®3 System Manual

Version 1.D

Figure 14. Interline CCD Readout ................................................................................... 51
Figure 15. Non-Overlapped Mode Exposure and Readout .............................................. 52
Figure 16. Full Frame CCD Readout ............................................................................... 54
Figure 17. Dual Port Readout: 2 × 2 Binning of Interline CCD ...................................... 57
Figure 18. Dual Port Readout: LightField Settings for 2 × 2 Binning of Interline CCD . 58
Figure 19. Single Port Readout: 2 × 2 Binning of Full Frame CCD ................................ 58
Figure 20. Experiment Setup|ROI Setup tab .................................................................... 59
Figure 21. Edit Regions of Interest window .................................................................... 60
Figure 22. Partial Frame 2 × 2 Binning for Interline CCD - Single Port Readout (ROI
does not have to be centered horizontally) ..................................................... 60
Figure 23. Dual Port Readout: LightField Settings for 5 × 3 Binning for Interline CCD 61
Figure 24. PI-MAX3 Setup| Hardware|Controller/Camera tab ........................................ 63
Figure 25. Comparison of Shutter {Shutter Open}, Read Out {Reading Out}, andAcquiring {Acquiring} Levels ....................................................................... 64
Figure 26. Experiment Setup|Main tab ............................................................................ 64
Figure 27. Experiment Setup|Timing dialog .................................................................... 65
Figure 28. Safe Mode and Fast Mode Operation ............................................................. 67
Figure 29. Common Acquisition Settings expander ........................................................ 68
Figure 30. Region of Interest expander............................................................................ 69
Figure 31. Trigger expander: Internal .............................................................................. 69
Figure 32. Trigger expander: External ............................................................................. 69
Figure 33. SuperSYNCHRO Timing expander ............................................................... 70
Figure 34. Timing: Bracket Pulsing ................................................................................. 74
Figure 35. PI-MAX3 Timing for MCP Bracket Pulsing .................................................. 76
Figure 36. Experiments with the PI-MAX3 ..................................................................... 77
Figure 37. Experiment is Master Clock: Hardware Setup and Timing Diagram ............. 78
Figure 38. Hardware Setup: Controller/ Camera tab ....................................................... 79
Figure 39. Define Spectrograph and Install/Remove Spectrographs dialogs .................. 80
Figure 40. Move Spectrograph dialog ............................................................................. 80
Figure 41. Experiment Setup: Main and Timing tabs ...................................................... 81
Figure 42. Experiment Setup: ADC and ROI Setup tabs ................................................. 81
Figure 43. SuperSYNCHRO: Trigger tab ........................................................................ 82
Figure 44. SuperSYNCHRO: Trigger In and Gating tabs ............................................... 82
Figure 45. Sequential Gating Setup and Width/Delay Sequence dialogs ........................ 83
Figure 46. Trigger Out tab ............................................................................................... 84
Figure 47. Experiment Setup: Timing and Main tabs ...................................................... 84
Figure 48. Experiment Results in 3-D ............................................................................. 85
Figure 49. PI-MAX3 SyncMASTER is Master Clock: Hardware Setup and Timing
Diagram .......................................................................................................... 86
Figure 50. Single Shot: Hardware Setup.......................................................................... 87
Figure 51. Cleans and Skips: Default Values Loaded ..................................................... 87
Figure 52. Experiment Setup: Gain Selected ................................................................... 88
Figure 53. Repetitive Gating Setup: 100 ns Width, 10 ns Delay ..................................... 88
Figure 54. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay .............. 89
Figure 55. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay, Binned
Vertically ........................................................................................................ 89
Figure 56. Repetitive Gating Setup dialog ....................................................................... 90
Figure 57. Timing: Bracket Pulsing ................................................................................. 94
Figure 58. PI-MAX3 Timing for MCP Bracket Pulsing .................................................. 96
Figure 59. Experiments with the PI-MAX3 ..................................................................... 96

Table of Contents

xi

Figure 60. Experiment is Master Clock: Hardware Setup and Timing Diagram ............. 98
Figure 61. Sensor Cleaning flyout pane ........................................................................... 99
Figure 62. Spectrometer expander ................................................................................... 99
Figure 63. Region of Interest expander: Full Sensor ..................................................... 100
Figure 64. Common Acquisition Settings expander ...................................................... 100
Figure 65. Analog to Digital Conversion expander ....................................................... 101
Figure 66. Trigger expander: Internal Trigger Source ................................................... 101
Figure 67. Region of Interest expander: Full Sensor Binned ......................................... 101
Figure 68. Trigger expander: External Trigger Source .................................................. 102
Figure 69. SuperSYNCHRO Timing expander ............................................................. 103
Figure 70. SuperSYNCHRO Timing with SyncMASTER On ...................................... 103
Figure 71. Experiment Results with Frame Cross Section ............................................ 104
Figure 72. PI-MAX3 SyncMASTER1 is Master Clock: Hardware Setup and Timing
Diagram ........................................................................................................ 105
Figure 73. Single Shot: Hardware Setup........................................................................ 106
Figure 74. Cleans and Skips: Default Values Loaded ................................................... 107
Figure 75. Experiment Setup: Gain Selected ................................................................. 107
Figure 76. Repetitive Gating Setup: 100 ns Width, 25 ns Delay ................................... 108
Figure 77. Single Shot Result: Fluorescence Spot, 100 ns Width, 25 ns Delay ............ 109
Figure 78. Single Shot Result: Fluorescence Spot, 100 ns Width, 25 ns Delay, Binned
Vertically ...................................................................................................... 109
Figure 79. SuperSYNCHRO Timing expander: Repetitive Gating Setup ..................... 110
Figure 80. Pulse Set ....................................................................................................... 111
Figure 81. Trigger per Pulse .......................................................................................... 111
Figure 82. Sequence with 3 Repetitions ........................................................................ 112
Figure 83. Timing Diagram: Sequence with 3 Repetitions and Trigger per Pulse ........ 112
Figure 84. System Diagram: DIF Operation .................................................................. 116
Figure 85. DIF Operation: Single Trigger Timing Diagram .......................................... 117
Figure 86. Hardware Setup|Controller/Camera tab........................................................ 117
Figure 87. Experiment Setup|Main and Timing tab ....................................................... 117
Figure 88. Pulsers dialog ............................................................................................... 118
Figure 89. Gating tab ..................................................................................................... 118
Figure 90. DIF Gating Setup dialog – Single Trigger.................................................... 118
Figure 91. Trigger In and Trigger Out tabs.................................................................... 119
Figure 92. System Diagram: DIF Operation .................................................................. 119
Figure 93. DIF Operation: Dual Trigger Timing Diagram ............................................ 120
Figure 94. Hardware Setup|Controller/Camera tab........................................................ 120
Figure 95. Experiment Setup|Main and Timing tabs ..................................................... 121
Figure 96. Pulsers dialog ............................................................................................... 121
Figure 97. Gating tab ..................................................................................................... 121
Figure 98. DIF Gating Setup dialog – Dual Trigger ...................................................... 121
Figure 99. Trigger In and Trigger Out tabs.................................................................... 122
Figure 100. Readout expander ....................................................................................... 123
Figure 101. Common Acquisition Settings expander .................................................... 124
Figure 102. Trigger expander ........................................................................................ 125
Figure 103. SuperSYNCHRO Timing expander: DIF ................................................... 125
Figure 104. DIF Hardware Connection diagram ........................................................... 126
Figure 105. DIF Single Trigger Mode Timing diagram ................................................ 126
Figure 106. DIF Hardware Connection diagram ........................................................... 128
Figure 107. DIF Dual Trigger Mode Timing diagram ................................................... 128

xii

PI-MAX®3 System Manual

Version 1.D

Figure 108. MCP Gated Operation Cabling .................................................................. 132
Figure 109. PI-MAX3 Timing in MCP Gated Operation .............................................. 133
Figure 110. PI-MAX3 Rear Panel ................................................................................. 146
Figure 111. Ebus Driver Installation Tool dialog .......................................................... 156
Figure 112. Ebus Driver Installation Tool dialog .......................................................... 156
Figure 113. AUX I/O Connector Pinout ........................................................................ 161
Figure 114. Intensifier QE Curves ................................................................................. 165
Figure 115. Outline Drawing: PI-MAX3 with C-mount Adapter .................................. 168
Figure 116. Outline Drawing: PI-MAX3 with F-mount Adapter .................................. 169
Figure 117. Outline Drawing: PI-MAX3 with Spectroscopy-mount Adapter ............... 170
Figure 118. Outline Drawing: PI-MAX3 Power Supply ............................................... 171
Figure 119. Outline Drawing: CoolCUBEII Circulator .................................................. 172
Figure 120. Extender Bracket Kit mounted to PI-MAX3 .............................................. 178
Figure 121. F-mount (Nikon) Lens Adapter .................................................................. 180
Figure 122. Screwdriver with Reversible Flat and Phillips tips. ................................... 182
Figure 123. PI-MAX3 Mount Adapters ......................................................................... 183
Figure 124. O-ring Positions for PI-MAX3 NVUV Cameras ....................................... 184

TablesTable 1. Readout Rates for Kodak 1024 × 1024 Array at 16 MHz Dual Port ................. 53
Table 2. Spectral Rates for e2v CCD30-11 Array at 2 MHz ........................................... 55
Table 3. Timing Mode, Shutter Control, and Ext. Trigger Input when using the Internal
Timing Generator............................................................................................... 73
Table 4. Single Shot Experiment Time Budget ............................................................... 87
Table 5. Timing Mode, Shutter Control, and Ext. Trigger Input when using the Internal
Timing Generator............................................................................................... 93
Table 6. Single Shot Experiment Time Budget ............................................................. 106
Table 7. Typical Picosecond Rates, Readout Times, and Gates/Frame for
PI-MAX3:1024i ............................................................................................... 136
Table 8. CCD Specifications.......................................................................................... 158
Table 9. AUX I/O Cable Leads...................................................................................... 161
Table 10. AUX I/O Connector Pinout and Signal Description ...................................... 162

Attention!
WARNING

Intensified CCD detectors, such as the PI-MAX®3, 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. If a sustained alarm indication occurs when the controller
is turned on, either completely cover the intensifier 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-MAX3 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 I.I.T. switch (on the back of the PI-MAX3) to the OFF
position. Cover the detector window and only switch the I.I.T. switch to ON after theillumination level has been lowered. If the alarm sounds continuously even when theillumination level is adequately low, shut the system down and contact the factory 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.

UnigenTMII Coating
For greater sensitivity, the PI-MAX3 camera with Unigen II coating comes without aprotective window over the intensifier. Do not scratch the image intensifier’s coatedsurface. To remove any lint or dust, use very clean dry nitrogen with < 5 PSI pressure. If
you have any questions please contact your sales contact or the factory.

xiii

xiv

PI-MAX®3 System ManualThis page intentionally left blank.

Version 1.D

Chapter 1
Introduction
The Princeton Instruments PI-MAX®3 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-MAX3
uses a proximity-focused microchannel plate (MCP) image intensifier (Gen II and
Filmless Gen III intensifiers available) fiber-optically coupled to a CCD array. The
fastest intensifiers can be gated in as little as 3 ns or less with an exceptionally highon/off light-transmission ratio. The CCD array provides a low noise, high dynamic range
readout device that can be scanned at a variety of pixel rates. A number of different
arrays are available to match the PI-MAX3 to the widest possible range of experimental
requirements. In operation, data acquired by the camera is routed to the computer forprocessing and display. The computer controls both the system configuration and dataacquisition via software, of which Princeton Instruments LightField® and WinView/32
are examples.

PI-MAX3 System Components
All PI-MAX3 systems consist of
standard hardware and software aswell as the appropriate interface
hardware for your computer
system.

CameraThe PI-MAX3 camera houses the
CCD and intensifier and it
supplies all of the high voltages
needed to operate the intensifier(see Chapter 3 for more
information).

Figure 1. Typical PI-MAX3 System Components

Cooling within the camera is performed by a cooling fan and a multi-stage Peltier coolerthat is thermally coupled to the CCD (liquid coolant circulation can also be used for the
PI-MAX3 camera). Photocathode cooling to reduce equivalent background illumination(EBI) can be achieved via a dry nitrogen source. C-, F-, and spectroscopy mount adapters
are supplied (one of which is factory-installed).
The camera can be operated in one of the following two modes: Safe mode and Gate mode.
In Safe mode, the photocathode is gated off. In Gate mode, the photocathode is biased on
only during the time each gate pulse is applied.
The PI-MAX3 contains the analog and digital electronics, scan control and exposure
timing hardware, and controller I/O connectors. Readout modes supported include full
resolution, simultaneous multiple subimages, and nonuniform binning. Single or multiple
software-defined regions of interest can also be tested without having to digitize all the
pixels of the array. Flexible exposure, set through software, is also fully supported.
15

PI-MAX®3 System Manual

16

Version 1.D

The PI-MAX3 contains two High Speed analog-to-digital converters. The effective
digitization rate is software-selectable. After the data is converted, it is transferred
directly from the camera to the host computer memory via the high speed interface cable.

Cable
AUX I/O Cable: 6050-0660, female DB26 to 5 BNC.

Computer Interface:Standard Ethernet Cable: 6050-0621, 5 meter. Other lengths up to 100 m areavailable.

User-provided GigE interface card. (Intel Pro1000 recommended)

TubingClear PVC tubing, 3’, 5/32” OD, 1/32” wall (McMaster-Carr 5006K42) for dry
nitrogen cooling of photocathode.

Manuals
PI-MAX3 System manual and optional application software manual.

Optional Application Software
Princeton Instruments' WinView/32 or WinSpec/32.
Princeton Instruments’ LightField

Summary of PI-MAX3 Data Acquisition

Figure 2. Major Components of the Intensifier-CCD

In the PI-MAX3 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. The image at

Chapter 1

Introduction17

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 internal controller, where it isdigitized, and then 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 high speed (GigE) serial interface cardis installed in the host computer. When reading through the sequence, keep in mind thatelectrons are attracted to more positively charged surfaces and are repelled by morenegatively charged surfaces. This principal is used to control electron flow through theintensifier tube: changing the photocathode voltage with respect to the voltage at the
MCP input is used to switch (gate) the intensifier on and off.
1. Incident photons pass through the intensifier input window, strike the photocathode,and release electrons. (see Figure 2)
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
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 (5-6 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) 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(s) where it isdigitally encoded. The conversion speed and the quality of the data are dependent on
the effective ADC rate.
9. The digitized information is transmitted from the camera through the Ethernet cableto 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.

* Units having a tapered fiber optic bundle may also be available. Contact the factory for

information.

PI-MAX®3 System Manual

18

Version 1.D

Safety Information
Safety Related Symbols Used in This Manual
Caution! The use of this symbol on equipment indicates that one or more
nearby items should not be operated without first consulting the manual.
The same symbol appears in the manual adjacent to the text that 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 andshould be regarded as potentially dangerous. This same symbol appears in
the manual adjacent to the text that discusses the hardware item(s) inquestion.

Grounding and Safety
The PI-MAX3 and power supply are of Class I category as defined in IEC Publication
348 (Safety Requirements for Electronic Measuring Apparatus). They are designed forindoor operation only. Before turning on the power supply, the ground prong of thepower cord plug must be properly connected to the ground connector of the wall outlet.
The wall outlet must have a third prong, or must be properly connected to an adapter thatcomplies with these safety requirements.
If the equipment is damaged, the protective grounding could be disconnected. Do not use

WARNING! 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.
The PI-MAX3 has internal power supplies that generate hazardous (and potentiallylethal) voltages. It contains no user-serviceable parts. Do not attempt to operate it withthe covers removed.

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
WinX Applications: The Experiment Setup Main screen in WinX applications allows
you to select one of two intensifier modes: Gate Mode or Safe Mode. 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 is higher in gated operation, but the risk ofdamaging overload from intense light sources such as lasers remains. In fact, intenselight sources in gated experiments can cause spot damage that would be undetectedby the alarm circuit. In Safe Mode, the photocathode is continuously biased OFF
and the intensifier is as safe as it can be.

Chapter 1

Introduction

19

LightField: In LightField, you can enable or disable the intensifier on the Common
Acquisition Settings expander. When the intensifier is enabled, the camera can begated; when disabled, the photocathode is continuously biased OFF and theintensifier is as safe as it can be.
Note: In order for gating to occur, the I.I.T. switch on the back of the PI-MAX3 mustalso be in the ON position.

Audible Alarm
Note: It is normal for the alarm to sound briefly when the system is turned on.
To reduce the risk of camera damage, the PI-MAX3 camera is equipped with an audible
alarm in the camera, activated when the intensity of light falling on the image intensifier
exceeds a preset threshold. While the alarm is sounding, the photocathode is disabled.
Immediately switch the I.I.T. switch on the back of the PI-MAX3 to the OFF position.
Cover the detector window and only switch the I.I.T. switch to ON after the illuminationlevel has been lowered. If the alarm sounds continuously even when the illuminationlevel is adequately low, shut the system down and contact the factory for guidance.
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.

High Intensity Light Damage
WARNING! Intensified CCD cameras such as the PI-MAX3, 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. If a sustained alarm indication occurs when the camera isturned on, immediately switch the I.I.T. switch on the back of the PI-MAX3 to the OFF
position. Cover the detector window and only switch the I.I.T. switch to ON after theillumination 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 PI-MAX3 power supply before changing yoursystem configuration in any way.
 Whenever you turn the PI-MAX3 power supply, 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.
 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.

PI-MAX®3 System Manual

20




Version 1.D

Never operate the camera cooled without proper evacuation or backfill. This could
damage the CCD! Do not open the purge valve.
Never connect or disconnect any cable while the PI-MAX3 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 Camera
Although there is no periodic maintenance that must be performed on the PI-MAX3 camera,users are advised to wipe it down with a clean dust collecting cloth from time to time.

Cleaning Optical Surfaces – UnigenTMII Coating
For greater sensitivity, the PI-MAX3 camera with Unigen II coating comes without aprotective window over the intensifier. Do not scratch the image intensifier’s coatedsurface. To remove any lint or dust, use very clean dry nitrogen with < 5 PSI pressure. If
you have any questions please contact your sales contact or the factory.

Cleaning Optical Surfaces – Protective Window
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 opticalsurface to be cleaned. Do not allow any other material to touch the optical surfaces.

Flushing and Refilling the CCD Chamber
Under normal conditions the CCD chamber is sealed and backfilled so there is no danger

WARNING! of damage due to condensation.

Operating a PI-MAX3 that is no longer backfilled with dry air or dry nitrogen may result

WARNING! in condensation on the array that could cause irreversible damage. Such damage would
not be covered by the Warranty.

Before a PI-MAX3 camera leaves the factory, its CCD chamber is backfilled with clean
dry air or dry nitrogen. For proper operation it is essential that the integrity of the front
enclosure be maintained.
In normal operation, the CCD chamber should remain sealed for the life of the detector
and should require no maintenance to assure integrity. If it should ever happen that theCCD chamber 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 205
for contact information.

Chapter 1

Introduction

21

Repairs
Save the original packing materials. Because the PI-MAX3 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 205 of this manual).
Use the original packing materials whenever shipping the system or system components.

About this Manual
Manual Organization
This manual provides the user with all the information needed to install a PI-MAX3
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 and appendices follows.
Notes:
1. “WinX” is a generic term for WinView/32, WinSpec/32, and WinXTest application
software.
2. In many instances, WinX and LightField use different terms for the same functions or
parameters. Unless the topic is specifically for WinX or LightField, curly brackets{ } are used to denote a LightField term or location. When the topic applies to both
application programs, the WinX term will be followed by the {LightField term}: forexample, when Continuous Cleans is used, it will be followed by {Clean Until
Trigger}. This convention is also used when a location for setting a parameter ismentioned: for example, Exposure Time is set on the Experiment Setup|Main tab{Common Acquisition Settings expander}.
Chapter 1, Introduction provides an overview of the PI-MAX3 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-MAX3 for both spectroscopy and imaging.
Chapter 4, First Light provides abbreviated directions for getting your PI-MAX3
into operation as soon as possible.
Chapter 5, General Operation Factors provides information about experiment
setup, temperature control, background subtraction, array readout, binning, anddigitization.
Chapter 6, WinX and Gated Operation discusses issues specific using WinX
and operating the PI-MAX3 system in gate mode.
Chapter 7, LightField and Gated Operation discusses issues specific using
LightField and operating the PI-MAX3 system in gate mode.
Chapter 8, Timing Generator Pulses and Sequences discusses andillustrates the trigger modes available when operating the system in gate mode.

22

PI-MAX®3 System Manual

Version 1.D

Chapter 9, WinX and Dual Image Feature (DIF) discusses using WinX with themode specifically designed for capturing a pair of gated images in rapid succession.
Chapter 10, LightField and Dual Image Feature (DIF) discusses using LightField
with the mode specifically designed for capturing a pair of gated images in rapid
succession.
Chapter 11, MCP Gating Option discusses how to set up a PI-MAX3 that has an
installed MCP Gating board.
Chapter 12, Sub-Nanosecond Option discusses how to set up a PI-MAX3 thathas an installed Sub-Nanosecond board.
Chapter 13, Tips and Tricks discusses a number of issues that can have a bearing
on getting good experimental results.
Chapter 14, System Component Descriptions describes the PI-MAX3 camera
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 PI-MAX3
camera, the PI-MAX3 power supply, and the CoolCUBEII coolant circulator.
Appendix C, Cross-Referencing of WinX and LightField Terms includes
two alphabetically sorted tables (WinX to LightField and LightField to WinX)
that cross reference terms used in the two applications.
Appendix D, Extender Bracket Kit explains how to use this kit to mount the
PI-MAX3 to any laboratory table with either 25 mm or 1 inch hole spacing.
Appendix E, Mounting and Focusing C-Mount and F-Mount Lenses
discusses focusing of an F-mount adapter and focusing of F-mount and C-mountlenses.
Appendix F, C-, F-, and Spectroscopy-Mount Adapters describes how tochange the adapter on the front of the PI-MAX3 to another type if you havemultiple adapters.
Appendix G, Spectrograph Adapters provides mounting instructions for the
spectroscopy-mount adapter and for the spectrograph adapters available for
PI-MAX3 cameras with spectroscopy-mounts.
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-MAX3
systems.
Warranty & Service details the warranties for Princeton Instruments equipment
and software.

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 fordetailed 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 25

2. Verify that all system components have been received.

Chapter 3: System Setup,
page 25

3. If the camera will be used on a spectrograph, mount it to theequipment using the required adapter(s).

Appendix G, page 186

4. If the appropriate interface card is not already installed in the hostcomputer, install it and its drivers.

Chapter 3: System Setup,
page 29

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

Application manual.

6. With the PI-MAX3 power supply and computer power turned OFF,connect the Ethernet cable (GigE) to the PI-MAX3 and the interface
card in the host computer.
7. Air-Cooled System: Plug the power supply into the rear of thecamera and plug the power supply into the power source.
Liquid-Cooled System: Make the hose and power connections tothe camera and plug the circulator into the power source. Add
coolant if necessary. Turn on the circulator.
8. If the photocathode will be cooled, connect the supplied PVC tubing
to the hose barb on the front of the camera and to a dry nitrogensource.

Chapter 3: System Setup,
page 29
Chapter 3; System Setup,
page 31

9. Turn the PI-MAX3 power supply ON.

23

24

PI-MAX®3 System Manual

Version 1.D

ActionReference

10. Turn on the computer and begin running the WinX or LightField
application. When the computer boots, you may be asked for thelocation of the interface drivers.
WinX: 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 enters this information as
the default parameters for your system.
LightField: When LightField boots, it will detect the camera andautomatically place its icon in the Available Devices area. Whenyou move that icon to the Experiment Devices area, the default
parameters will automatically be loaded into the expanders.

Chapter 3: System Setup,
page 31

11. 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 or edit that setup information.

WinView/32 or
WinSpec/32 manual
LightField manual

12. Set the target array temperature. The typical target temperature is-25°C.

Setting the Temperature,
page 48

13. When the system reaches temperature lock, begin acquiring data infocus mode.

Initial Data Acquisition,
page 37

14. 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. If you are using LightField, you may want to use the Align
Spectrometer function.

Appendix E: Mounting andFocusing C-Mount and FMount Lenses, page 180
Appendix G: SpectroscopyMount and Spectrograph
Adapters, page 186

WinView/32 or
WinSpec/32 manual
LightField manual (PDF)(Located in the Documents
subdirectory of the location
where LightField was
installed.)

Figure 3. PI-MAX3 System DiagramChapter 3
System Setup
Introduction
This chapter includes general instructions for setting up a PI-MAX3 system for operationin both imaging and spectroscopic applications.

Dangers and Warnings
DANGER

Voltages inside the PI-MAX3 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-MAX3 with its
covers removed.

WARNING

Image intensified detectors can be destroyed if exposed to excessive light levels.
Princeton Instruments cannot take responsibility for PI-MAX3 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-MAX3 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-MAX3
system. A typical system consists of:PI-MAX3 camera (Gen II or Filmless Gen III).



PI-MAX3 power supply.

Timing Generator: Integrated into the PI-MAX3

25

PI-MAX®3 System Manual

26

Version 1.DAccessory Kit: Contains light table mount extender, AUX I/O cable, PVC
tubing, double-ended screwdriver with magnet top, and two adapter mounts(C-mount, F-mount, and spectroscopy mounts are supplied, one of which has
been factory installed).

Computer Interface: GigEComputer: Provided by user.

WinView/WinSpec or LightField CD-ROM

User Manuals

Interface Dependent Components:Computer Interface GigE cable: Standard Ethernet Cable: 6050-0621,
5 meter. Other lengths up to 100 m are available.

Interface Card: User-provided GigE interface card. (Intel Pro1000
recommended).

System Dependent Components


CoolCubeII Coolant Circulator and Coolant Tubing

If there are any problems, contact the Princeton Instruments Customer Support
department (see page 205 for contact information).

System Requirements
Environmental
Storage temperature 55°C
Operating environment temperature: 30°C > T > -25°C
Relative humidity <80% noncondensing

Ventilation
Camera: Allow at least one-inch clearance for side and rear air vents. There are internalfans located behind an intake opening in the rear panel. Their purpose is simply
to cool the camera and TE-cooler. The fans run continuously whenever thecamera is powered. Air enters the through the openings in the rear panel and isexhausted through ventilation openings on the side panels. It is important that
there be an adequate airflow for proper functioning. As long as both the camera’s
intake ventilation openings and the fan exhaust opening aren’t obstructed, thecamera will remain quite cool.
Power Supply: There is an internal fan located at the rear panel behind an exhaust
opening. Its purpose is simply to cool the power supply electronics. This fan runs
continuously whenever the power supply is powered. Air enters the throughventilation openings in the side panels, flows past the warm electronics, and isdrawn out the rear by the fan. It is important that there be an adequate airflow for
proper functioning. As long as both the intake ventilation openings and the fan
exhaust opening are not obstructed, the power supply will remain quite cool.

Chapter 3

System Setup

27

Power
Camera: The PI-MAX3 camera receives its power from the self-switching power supply
which in turn plugs into a source of AC power.
Power Supply: 90-264 VAC, 400W (Max.), 47-63 Hz, auto-switching. The plug on the
power cord supplied with the system should be compatible with the line-voltage
outlets in common use in the region to which the system is shipped. If the power cordplug is incompatible, a compatible plug should be installed, taking care to maintainthe proper polarity to protect the equipment and assure user safety.
Caution

Whenever you turn the PI-MAX3 power supply OFF, be sure to leave it OFF for atleast 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.












Operating System: WinView/32 and WinSpec/32: Windows® XP (32-bit with SP3 or later),Windows Vista® (32-bit) or Windows 7® (32-bit) LightField: Windows Vista (64-bit) or Windows 7 (64-bit)
2 GHz Pentium® 4 (or greater)
1 GB RAM (or greater)
CD-ROM drive
At least one unused PCI card slot (32-bit) (PCI 2.3 compliant 32-bit 33/66 MHz bus)
Super VGA monitor and graphics card supporting at least 65535 colors with atleast 128 Mbyte of memory. Memory requirement is dependent on desired
display resolution.
Hard disk with a minimum of 1 Gbyte available. A complete installation of the
program files takes about 50 Mbytes and the remainder is required for data
storage, depending on the number and size of images/spectra collected. Disk
level compression programs are not recommended. Drive speed of 10,000 RPM
recommended.
Mouse or other pointing device.

Note: The above requirements are the minimum for operating a PI-MAX3 camera. A
faster computer with 2GB or larger memory (RAM) and a fast hard drive (10,000 rpm)
will greatly enhance the software performance during live mode operations.

PI-MAX®3 System Manual

28

Version 1.D

Mounting the PI-MAX3
Imaging Applications
The PI-MAX3 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 secured
by four (4) Phillips head screws which must be removed to change mounts. Refer toAppendix E: Mounting and Focusing C-Mount and F-Mount Lenses, Appendix F: C-,F-, and Spectroscopy-Mount Adapters, and Appendix G: Spectrograph Adapters for more
information for changing mounts and focusing.
The PI-MAX3 can be mounted at any attitude or angle but additional camera support may
be required. The camera can rest on any secure surface. Take care not to block theventilation openings.

WARNINGIn 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. Be sure liquid connections do not leak in this orientation.

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-MAX3 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 the “Quick
Start: Mounting a PI-MAX3 (3.60 3-hole Slotted) to an Acton Series Spectrograph”
instructions supplied with your system and also provided in Appendix G.

Chapter 3

System Setup

29

Software Installation
WinX
Notes:
1. Install the GigE Adapter card BEFORE installing the WinView/32 or WinSpec/32
application software.
2. Leave the interface cable disconnected from the camera until you have installed
WinView/32 or WinSpec/32 (Ver. 2.5.25 or higher).
The following installation is performed via the WinView/32 or WinSpec/32 software
installation CD.
1. On the Select Installation Typedialog (see Figure 4), click on
Typical radio button to install therequired drivers and the mostcommonly installed program files.
Select the Custom radio button if
you would like to choose among
the available program files or do
not want to install the drivers.
Complete installs all of theapplication features.
2. Make sure the camera isconnected to the host computer
and that the camera power supply
is turned on.

Figure 4. WinView Installation:
Select Installation Type dialog

3. Reboot the computer.
4. At bootup, Windows will detect the GigE card. Refer to “WinX First Light
Instructions” on page 34.

LightField
Note: Install the GigE Adapter card BEFORE installing the LightField application
software.
The following installation is performed via the LightField software installation CD.
1. Before starting the installation:
 Verify that the computer operating system is Windows Vista (64-bit) orWindows 7 (64-bit).
 Confirm that a GigE adapter card has been installed.
 Verify that your computer is connected to the Internet. Internet connection isrequired for product activation.
2. Insert the CD and follow the installation wizard prompts.

30

PI-MAX®3 System Manual

Version 1.D

Figure 5. LightField Installation Wizard dialog

3. After the installation finishes, reboot the computer.
4. Connect the PI-MAX3 system components to your computer and power them on.
5. Start LightField, activate it, and begin setting up your experiment. Refer to“LightField First Light Instructions” on page 38

Making the Camera-Circulator Connections
For liquid-cooled cameras, the CoolCUBEII circulator provides a vibration-free methodof heat removal.
1. Make sure the camera and the circulator power switches areturned off.
2. Make sure the circulator is 6 inches (150 mm) or more below
the camera. The vertical distance should not exceed 10 feet (3m). Typically, the camera is at table height and the circulator
is on the floor.
3. Make the coolant connections between the circulator and thecamera. It does not matter which hose from the circulator isplugged into a coolant port on the camera.
4. It is recommended that hoses be secured to the camera hose barbs with the clamp
supplied.
Notes:
1. Make sure that there are no kinks in the hoses that impede the coolant flow. Lackof sufficient flow can seriously harm the detector and any resulting damage is notcovered under warranty.
2. Damage caused by water leaking into the PI-MAX3 voids the warranty.
5. Unscrew the reservoir cap (on top of the CoolCUBE II) and make sure that thecoolant reservoir contains coolant. If additional coolant is required, fill with a 50:50
mixture of water and ethylene glycol.
6. Screw the reservoir cap back in.
7. Plug the circulator into a 100-240 VAC, 47-63 Hz power source.
8. Turn the circulator on. Make sure there are no leaks or air bubbles in the hoses.

Chapter 3

System Setup

31

Note: Small air bubbles (about the size of bubbles in soda) are common in the
CoolCUBEII especially at start up and do not prevent proper operation

If there are no problems, continue to Step 9.
If there are leaks or air bubbles, turn the circulator off and correct the problem(s)by securing the hoses or adding more coolant to the reservoir. Turn the circulator
back on. Recheck and if there are no problems, continue to Step 9.
9. Turn the camera on.
10. Start the application software.

Making the Camera to Dry Nitrogen Source Connections
Equivalent Background Illumination (EBI) can impose limitations on ultra-low-light orphoton-counting applications. Reduction of EBI can be achieved by directly cooling thephotocathode via a dry nitrogen source.
1. Remove the 3 foot (approximately 1 meter) clear PVC tubing from the accessories
kit.
2. Slip one end of the tubing on the plastic hose barb on the front of the PI-MAX3.
3. Connect the other end to a source of dry nitrogen.

Entering the Default Camera System Parameters
WinX (Versions 2.5.25.X or higher)
1. Make sure the PI-MAX3 is connected to the host computer and that its power supply
is turned ON.
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 6), leave the checkbox unselected and click on
Next.

Figure 6. Camera Detection Wizard - Welcome dialog

PI-MAX®3 System Manual

32

Version 1.D

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.
Note: For a step-by-step procedure on basic system operation, refer to the “WinXFirst Light Instructions” section (page 34).

LightField
1. Make sure the PI-MAX3 (and spectrograph, if this is a spectroscopy system) isconnected to the host computer and that the camera (and spectrograph) power
supply is turned on.
2. Start LightField.
3. While LightField is starting up, it will detect the available device(s) and load theappropriate icons into the Available Devices area in the Experiment workspace.
4. When you drag an icon into the Experiment Devices area, the appropriate
expanders will be loaded into the Experiment Settings stack on the lefthand sideof the window.
Note: For a step-by-step procedure on basic system operation, refer to the“LightField First Light Instructions” section (page 38).

Chapter 4First Light
Introduction
This chapter contains two procedures (one for WinX and one for LightField) that can be used
to verify PI-MAX3 system operation. To reduce setup complexity, these procedures are run
in Imaging Mode and SuperSYNCHRO™ Internal Trigger Mode. All of the setup can be
performed under normal lighting. Since these first light procedures do not require aspectrograph, instructions for cabling and mounting of a spectrograph are not included.
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 5 and thosethat are specific 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-MAX3
camera system in accordance with the procedure in this chapter.
Princeton Instruments PI-MAX3 camera with C-mount adapter.

User-supplied C-mount lens (with smallest aperture of f/16 or f/22).



PI-MAX3 power supply.

Computer equipped with a GigE Ethernet interface card.

Standard Ethernet cable.



Application software (WinX/32 or LightField)

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 Gating Mode with aninternal trigger.
1. Connect the PI-MAX3 power supply to the rear of the camera and to the AC powersource.
2. Connect the GigE cable (6050-0621) from the PI-MAX3 GigE connector to thecomputer’s GigE Interface card connector.

33

PI-MAX®3 System Manual

34

Version 1.D

Before Turning on the System
1. Set the PI-MAX3 I.I.T. On/Off switch to OFF.
2. Confirm that only room light will be present.
3. If a C-mount adapter is not on the camera, refer to “Appendix F
C-, F-, and Spectroscopy-Mount Adapters”, page 182, for changeover instructions.
4. After making the changeover, screw in the lens. Set the lens to its smallest aperture(f/16 or f/22).
5. Place a suitable target (non-light source) approximately 9 inches in front of the camera.

Turning on the System
WARNING

Always begin with the lens stopped all the way down (largest f/ stop number) tominimize the risk of overloading the intensifier.
1. Turn on the PI-MAX3 power supply.
Note: The PI-MAX3 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 camera (or spectrograph, something is wrong. Turn off thepower and contact the factory for guidance.
2. Turn on the computer power.
3. Start the software application (WinView/32, WinSpec/32, or LightField asappropriate).
4. Follow the appropriate first light instructions.

WinX First Light Instructions
Introduction
This section provides step-by-step instructions for acquiring an imaging measurement in
WinX for the first time. The intent of this procedure is to help you gain basic familiarity
with the operation of your system and to show that it is functioning properly. Once basic
familiarity has been established, then operation with other operating configurations, ones
with more complex timing modes, can be performed.

Assumptions
The following procedure assumes that
1. You have already set up your system in accordance with the instructions in theprevious chapters.
2. You have read the previous sections of this chapter.
3. You are familiar with the application software.
4. The system is being operated in imaging mode.
5. The target is a sharp image, text, or a drawing that can be used to verify that thecamera is “seeing” and can be used to maximize focus.

Getting Started
1. Verify that you have a test target approximately 9 inches in front of the camera.
2. Power ON the camera (the power switch is on the back of the power supply).

Chapter 4First Light
3. Turn on the computer power.
4. Start the application software.

Configuring the Software
Setup menu
1. From the Setup menu, select Pulsers.
2. On the Pulsers dialog, select SuperSYNCHRO
and then click on the Setup Pulser… button.

3. On the Trigger In tab, confirm that Internal isselected and that the Frequency is 10000 Hz.

4. On the Gating tab, select Repetitive and thenclick on the Setup… button.

5. On the Repetitive Gating Setup dialog, enter
the following settings:
Gate Width: 50 ms
Gate Delay: 10 ns
Gates per Exposure: 1
Repeat Width/Delay: 1.

6. Click on OK.

35

36

PI-MAX®3 System Manual
Acquisition menu
1. From the Acquisition menu, select Experiment
Setup.
2. On the Main tab, make the following settings.
CCD Readout: Use Full Chip
Intensifier
Gain: 1Gate Mode: selected

3. On the ADC tab, select the appropriate Rate
(16 MHz for Kodak 1024x1024, 1 MHz for
CCD30-11).

Version 1.D

Chapter 4First Light37

4. If you are running WinSpec, select Imaging
Mode on the ROI Setup tab.

5. Click on OK to execute the selections and close the dialog.

Initial Data Acquisition
1. Verify that room or ambient lighting is subdued.
2. Set the PI-MAX3 I.I.T switch to ON.
Note: The PI-MAX3 overload alarm may sound briefly and then stop. This is normal
and is not a cause for concern. However, if the alarm sounds repetitively, even withno light entering the lens, something is wrong. Turn off the power and contact thefactory for guidance.
3. At the computer, click on the ACQ buttonor select Acquire mode (WinX
Acquisition menu). Data acquisition will begin and an acquired image will be
displayed on the computer monitor. If one is not displayed, check the softwaresettings.

4. If an image is displayed, you have confirmed that the PI-MAX3 can acquire animage. If the image is out of focus, you could reposition the target and/or rotate thelens and click on Acquire to confirm that the degree of focus has changed.
5. If the image is upside down (acquired with an older PI-MAX3:1024x256 camera as in
the image above), you can either physically invert the camera or you can change thePI-MAX®3 System Manual

38

Version 1.D

image orientation via the Setup|Hardware|Hardware Setup|Display tab. After
Reverse and Flip were selected and a new image was acquired, the text was rightreading.

6. Now that you have confirmed that the PI-MAX3 can acquire an image, set the
PI-MAX3 I.I.T. switch to OFF.
7. Close the WinX application.
8. If you do not want to use the PI-MAX3 with the lens, replace the C-mount lens withthe screw-in dust cover provided with the C-mount adapter.
9. If you will be using a different adapter, you can switch adapters at this point. Be sure
to use the adapter’s dust cover whenever the PI-MAX3 is not being used.

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

LightField First Light Instructions
Introduction
This section provides step-by-step instructions for acquiring an imaging measurement inLightField for the first time. The intent of this procedure is to help you gain basic
familiarity with the operation of your system and to show that it is functioning properly.
Once basic familiarity has been established, then operation with other operating
configurations, ones with more complex timing modes, can be performed.

Assumptions
The following procedure assumes that
1. You have already set up your system in accordance with the instructions in theprevious chapters.
2. You have read the previous sections of this chapter.
3. You are familiar with the application software.
4. The system is being operated in imaging mode.
5. The target is a sharp image, text, or a drawing that can be used to verify that thecamera is “seeing” and can be used to maximize focus.

Getting Started
1. Verify that you have a test target approximately 9 inches in front of the camera.

Chapter 4First Light
2. Power ON the camera (the power switch is on the back of the power supply).
3. Turn on the computer power.
4. Start the application software.

Setting the Parameters
Note: The following procedure is based on LightField. Basic familiarity with theLightField software is assumed. If this is not the case, you may want to review thesoftware manual or have it available while performing this procedure.

Figure 7. Available Devices Area

1. After LightField opens, you should see an icon representing your camera in the
Available Devices area. In the figure above, the camera is a
PI-MAX3:1024x256.
2. Drag the icon into the Experiment Devices area.

39

PI-MAX®3 System Manual

40

Version 1.D

Figure 8. Experiment Devices Area

3. Note that the Experiment Settings stack on the left now displays several
expanders, including the SuperSYNCHRO Timing expander just above theStatus bar (at the bottom of the window). Because this is a new experiment, thedefault settings for the camera will be active. The Status bar displays an icon fortemperature and intensifier status.
Temperature status reports the current temperature and whether the set
temperature has been reached. Intensifier status reports whether or not the I.I.T.
Power switch (on the rear of the camera) is turned on and whether the Enable
Intensifier check box is checked. Clicking on an icon opens a panel where you
can view more information about the status and/or click on a hyperlink to accessthe expander where status affecting changes can be made.
4. PI-MAX3:1024x256 Camera: If the camera was built before January 2012,
these additional steps are required for the 1024x256 camera.
a. Open the Online Corrections expander.
b. Click on the bottom button on the Orientation image.
oc. The icon will rotate 180 (see image below). Unless you subsequently change
the orientation or create a new experiment, data will be displayed correctly.
Note: A new experiment resets all of the camera
parameters to their default settings. Therefore, theorientation for a PI-MAX3:1024x256 camera must be
corrected whenever a new experiment is created.

Acquiring Data
1. Verify that the I.I.T. Power switch on the rear of the camera is in the ON
position
2. Verify that Enable Intensifier is selected on the Common Acquisition
Settings expander.

Chapter 4First Light41

3. Click on the View tab, just above Experiment Devices, to change to the display
area.

Figure 9. View Area

4. Click on the Acquire button
to start Acquire mode.
 If an image is displayed, you have confirmed that the PI-MAX3 can acquire
an image.
 If the image is out of focus, you could reposition the target and/or rotate thelens and click on Acquire to confirm that the degree of focus has changed.
 If the image is upside down, you need to change the orientation via theOnline Corrections expander.

Figure 10. View Area Displaying an ImagePI-MAX®3 System Manual

42

Version 1.D

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

Final Comments
This completes the First Light directions. If you have followed the instructions, you
should have verified the basic operation of your system. Subsequent chapters provide
general and specific information about operating a PI-MAX3 system.

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 Gate Mode operation of the
PI-MAX3 system. These factors play a part before, during, and after the exposure andreadout of the CCD array: dark charge, clean cycles, continuous cleans, exposure modes,
readout, digitization, software binning, and background subtraction. 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 (may include multiple gates), the charge from the arraypixels must be read out, digitized, and transferred to the computer before the image from thearray appears on the computer screen. This sequence is shown in the block diagram below(Figure 11).

Figure 11. Block Diagram of Signal Path in Standard PI-MAX3 System

43

PI-MAX®3 System Manual

44

Version 1.D

WinX System On/Off Sequences
The following on/off sequences are specific to WinX and the Ethernet interface:
1. The PI-MAX3 power supply must be turned on before the WinX application
software (WinView/32 or WinSpec/32) is opened to ensure communication between
the controller and the computer. If the WinX application is opened and the
PI-MAX3 power supply is off, many of the functions will be disabled and you will
only be able to retrieve and examine previously acquired and stored data. You mustclose the WinX application software, turn on the power supply, 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 power supply.
If you turn off the power supply before closing the WinX application software, thecommunication link with the PI-MAX3 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 power supply, 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 has power, whether or not the intensifier is being
gated to take an exposure. If the intensifier is off, dark charge 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 the camera is waiting to acquire thesignal of interest. Dark charge, clean cycles, and continuous clean cycles are described in
the paragraphs that follow.

Dark Charge
As soon as the PI-MAX3 camera is powered on, thermally-induced charge will begin
integrating on the CCD array even if the photocathode is biased off. Because dark charge
is thermally-induced, reducing the array temperature significantly reduces the rate at
which this charge accumulates in the pixel wells. Even so, enough dark charge could
accumulate in the pixels between data acquisitions to affect dynamic 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 PI-MAX3 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, both the signal of interest and dark charge integrate on the array.
The longer the exposure and the warmer the camera, the larger and less uniform the darkcharge will appear. To minimize the dark charge contribution to the acquired signal, you
should operate with the lowest temperature possible for your camera. Reducing the gate width
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
data acquired using the same experiment conditions (see “Background Subtraction”,
page 50).

Chapter 5General Operation Factors

45

Note: Do not be concerned about either the DC level of this background noise or its
shape unless it is very high, i.e., > 1000 counts with 16-bit A/D. What you see is notnoise. It is a fully subtractable readout pattern. Refer to “Background Subtraction”,
page 50, for more information.
If you observe a sudden change in the baseline signal you may have excessive humidity

WARNING! in the camera's CCD enclosure. Immediately turn off the controller. Then, contact
Princeton Instruments Customer Support for further instructions. See page 205 forcontact information.

Cleaning
The basic cleaning function is implemented by clean cycles. These cycles start when you
turn the camera on and a clean pattern is programmed into the camera. Their purpose is toremove charge that accumulates on the array while the camera not acquiring data (i.e.,
exposing and reading out the array). The timing diagram below is for an experiment set up
to acquire three (3) images using Internal trigger mode selected on SuperSYNCHRO
Trigger In tab {Trigger expander} and Gate Mode selected on Experiment Setup Maintab {In LightField, the equivalent of Gate Mode is active when Enable Intensifier ischecked on the Common Acquisition Settings expander}. 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 12. Clean Cycles in Internal Trigger Mode of Operation

The configuration of clean cycles is performed on the Hardware Setup|Cleans/Skipstab {via the Sensor Cleaning pane accessed on the Sensor expander}. When you set
up the camera for the first time, default values are automatically inserted into these fields.
These will give the best results for most applications. Even so it is a good idea to knowwhat these entries mean with regard to cleaning.


Number of Cleans {Number of Clean Cycles} value is usually set to one (1).
These are additional clean cycles that can be required after a start exposure signal
is received and the current clean cycle has finished. The maximum value for thisentry depends on the camera.



Number of Strips per Clean {Clean Cycle Height} sets the number of rows thatwill be shifted and discarded per clean cycle. While a large number such as thenumber of rows in the array may result in the best cleaning of the array, the tradeoff
is that there may be a significant delay between the receipt of a start exposure signal
and the beginning of the actual exposure. This delay occurs because the current clean
cycle must be completed before a start exposure signal received during the cycle will
be implemented. Typically, the default setting is much smaller and in time criticalexperiments, the setting should be 1 or 2.

PI-MAX®3 System Manual46Version 1.D

Clean Before Exposure {Clean Before Exposure} is only provided for camerasthat have a Frame Transfer CCD and is only available for selection when in Full
Frame mode is active. Normally, cleaning occurs until the acquisition starts.
When Clean Before Exposure is active, cleaning occurs up until acquisition
starts and the entire CCD will be cleaned once right after the readout occurs. It isa clean operation for the next exposure and it matters only when multiple images
are taken with a short exposure time.
Note: Clean Before Exposure is NOT relevant when you are in a triggered
mode.



Continuous Cleans {Clean Until Trigger} is available when the start of exposure
is tied to an external trigger. In WinX, this cleaning becomes active when
External Sync timing mode is selected. In LightField, it becomes active when
Trigger Response is set to Readout Per Trigger or Shift Per Trigger.



Skip Serial Register Clean (deselected) {Clean Serial Register} The Top margin
inactive parallel strips on a CCD are made up of the dark pixels that come before theactive strips on a sensor as they exit to the serial register. When these are available(i.e., Pre Dummies {Top Margin} > 0), they serve the purpose of cleaning the serial
register before readout of the active strips. In LightField, if there are no inactive
parallel strips (i.e., {Top Margin} = 0), selecting Clean Serial Register forces aclean of the serial register before readout of the active strips.

Note: The start of the exposure is signaled by the Read Out {Reading Out} output of
the LOGIC OUT connector going low but will not occur until the current clean cycle andthe additional user-defined number of cleans (typically 0) have finished. “Number ofCleans” is defined on the Setup|Hardware|Cleans/Skips tab {Sensor Cleaning
flyout pane on Sensor expander}. If you enter a value other than “0”, you will further
delay the start of the exposure by that number of clean cycles.

Chapter 5General Operation Factors

47

Phosphor Decay Delay
The WinX and LightField applications allow you to enter a delay between the end of the
exposure time and the beginning of the array readout. This time is inserted to allow thephosphor to decay to 1% before readout occurs and will vary depending on the phosphor
type. This delay has no effect on the actual time it takes for the phosphor to decay.
Note: In the case of an experiment using a PI-MAX3:1024i and a very short exposure
time, artifacts will appear in the first frame unless the phosphor decay delay is set to
3 ms. This amount of delay will ensure that the vertical registers (under the mask) arecleared before the acquired signal is shifted under the mask.

Enter phosphor
decay delay time
here.

Figure 13. WinX: Phosphor Decay Delay

LightField: Phosphor Decay Delay (Common Acquisition Settings|Advanced)

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 fans and exhausted through the side-panel grill. The fans arealways running and cooling the CCD and the internal electronics. Additional heat removal
can be performed by circulating coolant through an internal heat block.
Air-cooling: With air-cooling alone, at an ambient temperature of 25C, temperaturelock at -25 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

48

PI-MAX®3 System Manual

Version 1.D

smaller arrays). Also, if the lab is particularly warm, achieving temperature lockmight take longer or not be obtainable at all.
Supplemental Circulating Coolant: Allows temperature lock to be achieved more
rapidly than would be required to lock at the same temperature with air-coolingalone. In addition, it will be possible to achieve temperature lock at lower
temperatures, typically three or four degrees lower than would be possible with aircooling alone. Use the Princeton Instruments CoolCUBEII coolant circulator. It is a
closed circulation system that depends on ambient air-cooling of the circulating
coolant. Unless the laboratory has high humidity, the ambient temperature coolant
should prevent condensation inside the PI-MAX3. See “Making the CameraCirculator Connections”, page 29 for CoolCUBEII setup instructions.

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-MAX3. This condensation can cause catastrophic failure of the camera 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-MAX3 be operated where the humidity is
low enough to prevent internal condensation. If the coolant is below the freezing temperatureof water, 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-MAX3 inside a closed container and to then purge the container with a continuous
flow of dry nitrogen. On completion of the experiment, be sure to continue the purge
until the PI-MAX3’s internal cold surfaces have had time to warm to the ambientlaboratory temperature. Contact the factory if you require additional information.

Setting the Temperature
Regardless of the type of cooling, the CCD array temperature is set via the application
software. When WinX is the controlling software, temperature control is done via Setup|Detector Temperature menu choice. When Light Field is being used, temperature control
is done on the Sensor expander.
Once the target (desired) array temperature {Temperature Setpoint} has been set, thesoftware controls the camera's cooling circuits to reach set array temperature. On
reaching that temperature, the control loop locks to that temperature for stable andreproducible performance. When the Target Temperature {Temperature Setpoint} hasbeen reached, the current temperature is Locked. The on-screen indication allows easy
verification of temperature lock.
Temperature lock to a set temperature in the operating range will typically occur within
ten minutes. Another five minutes will be required for maximum temperature stability to
be achieved.
Note: The WinX Detector Temperature dialog will not display temperature
information while you are acquiring data.

Chapter 5General Operation Factors

49

Exposure
Introduction
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 associatedwell. Once charge accumulates for the exposure time (via gating sequences defined in theapplication software), the pixels 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-MAX3
rely on gating the intensifier off, to prevent light from reaching the array. During eachdata acquisition, the intensifier is gated on and off (this may happen a number of times if
there are multiple gates per exposure) to allow the pixels to register light during the “on”
period. It is gated off for the readout period.

Exposure with an Image Intensifier
PI-MAX3 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 bysoftware in this case refers to duration of gating of the intensifier.
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 background illumination (EBI).

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.” If this is the case, you could reduce the intensifier gain or read out
more frequently, with signal averaging to enhance S/N (Signal-to-Noise ratio)
accomplished through the software.

CautionSignals large enough to bloom may damage the intensifier.
For signal levels low enough to be readout-noise limited, longer exposures, and therefore
longer signal accumulation in the CCD, will improve the S/N ratio approximately linearlywith 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 lossof dynamic range due to the buildup of dark charge in the pixels.

PI-MAX®3 System Manual

50

Version 1.D

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, gating sequences, region of interest,
timing mode, etc.) and then, while blocking the incoming signal from the array, acquire adark charge “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.


Automatic: In WinX, this approach requires that you activate “Background” and specify
the background filename on the Acquisition|Experiment Setup…|Data Corrections
tab before acquiring an image. In LightField, you must check the Apply Background
Subtraction box on the Online Corrections expander and select the appropriate
background file or acquire a new background. When you acquire an image, the specified
background will be subtracted automatically 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 {Apply Background Subtraction box is not checked}. Then,acquire the image, save the raw image data to disk. In WinX you would then use the
Image (or Spectra) Math function (accessed from the Process menu) to subtract abackground data file from the raw image data: the resulting data can then be saved todisk in a separate file. In LightField you would open the data in the Data
Workspace, select Background… from the Processes dropdown list, choose theappropriate background file, click on Preview, and then click on OK: you can now
click on the Save button, edit the filename if desired, and save the data to disk.

Readout of the ArrayAt the end of the exposure, the charge from the pixels is shifted to the shift register, amplified,and digitized. Depending on the experiment design, binning may also occur as part of thereadout operation.


For the PI-MAX3:1024i camera and WinX, dual port readout mode is selected wheneverfull image readout is selected or when the region of interest (ROI) is defined to be
horizontally symmetrical and centered. Single port readout is activated when the ROI is
not horizontally symmetrical and centered. The same rules apply whether or not binningis utilized. Readout in single port mode may be slower than dual port mode readout. The
port used for single port mode is dictated by the CCD design.

For the PI-MAX3:1024i camera and LightField, when 2 port readout is selected, you
can acquire either a full image or a region of interest (ROI) defined to be horizontallysymmetrical and centered. If the ROI is not horizontally symmetrical and centered,single port readout must be selected. The same rules apply whether or not binning isutilized. Readout in single port mode may be slower than dual port mode readout.
The port used for single port mode is dictated by the CCD design.

For the PI-MAX:1024x256, signal is read out of a single port.

Chapter 5General Operation Factors

51

Interline CCD Readout
In this section, a simple 6  3
pixel interline CCD is used todemonstrate how charge is shiftedand digitized using a single port.
As described below, two different
types of readout, overlapped andnon-overlapped can occur. In
overlapped operation, eachexposure begins while the readoutof the previous one is still inprogress. In non-overlapped
operation (selected automaticallyif the exposure is shorter than thereadout time) each readout goesto completion before the next
exposure begins.

Figure 14. Interline CCD Readout

Non-Overlapped Operation Exposure and Readout
Figure 15 illustrates exposure and readout when operating in the non-overlapped mode.
Non-overlapped operation occurs automatically any time the exposure is shorter than thereadout time. Figure 15 contains four parts, each depicting a later stage in the exposurereadout cycle.
Part 1 of the figure shows the array early in the exposure. The imaging areas contain charge
proportional to the amount of light integrated on each of them. The masked (storage) areas
are empty because no charge has been transferred to them. The arrows between adjacentimaging and masked areas indicate the direction the charge will be shifted when the transfer
occurs.
Part 2 of Figure 15 shows the situation early in the readout cycle. The charge in the imaging
areas has been transferred to the adjacent masked areas and up-shifting to the readout
register has started. Note that a second exposure does not begin while the readout is inprogress because the intensifier is not gated on at this time.
Part 3 of Figure 15 shows the transfer to the output node. The lowermost pixel 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 image
intensifier is off during this time so no signal charge is accumulated, but dark current
does accumulate. Because this scheme is less time efficient than that used in theoverlapped mode, the frame rate may be lower in non-overlapped operation than it is inoverlapped operation with the some gating setups.
Part 4 of Figure 15 illustrates the situation at the end of the readout. Both the imaging andstorage areas are empty. When the intensifier is gated on again, signal charge will again
be accumulated.

52

PI-MAX®3 System Manual

Version 1.D

Figure 15. 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).

Chapter 5General Operation Factors

53

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 an entire frame at full
resolution in non-overlapped timing mode is:tR + texp

(1)

where
tR is the CCD readout time,
texp is the exposure time.
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-MAX3:1003 Kodak 1024 × 1024
interline array running at 16 MHz is shown in Table 1.
Region of Interest Size
Binning1024 × 1024

400 × 400

200 × 200

1x1

25.8

36.2

42.5

2x2

56.3

49.5

50

4x4

94.5

58.7

54.6*

*ROI increased to 202x200 to accommodate GigE rules.

Table 1. Readout Rates for Kodak 1024 × 1024 Array at 16 MHz Dual Port

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).

54

PI-MAX®3 System Manual

Version 1.D

Full Frame CCD Readout
The PI-MAX3:1024x256 camera
uses a full frame CCD for dataacquisition. The upper left drawing
in Figure 16 represents a CCD after
exposure but before the beginningof readout. The capital lettersrepresent different amounts ofcharge, including both signal anddark charge. This section explains
readout at full resolution, where
every pixel is digitized separately.
Readout of the CCD begins with thesimultaneous shifting of all pixels
one row toward the “shift register,”in this case the row on the bottom.
The shift register is a single line of
pixels along the edge of the CCD,
not sensitive to light and used forreadout only. Typically the shift
register pixels hold twice as muchcharge as the pixels in the imaging
area of the CCD.
After the first row is moved into the
Figure 16. Full Frame CCD Readout
shift register, the charge now in theshift register is shifted toward the output node, located at one end of the shift register. As
each value is “emptied” into this node it is digitized. Only after all pixels in the first row
are digitized is the second row moved into the shift register. The order of shifting in our
example is therefore A1, B1, C1, D1, A2, B2, C2, D2, A3....
After charge is shifted out of each pixel the remaining charge is zero, meaning that thearray is immediately ready for the next exposure.

Chapter 5General Operation Factors

55

Below are the equations that determine the rate at which the CCD is read out.
The time needed to take a full frame at full resolution is:t R  texp  tc

(1)

where
tR is the CCD readout time,
texp is the exposure time, andtc is the phosphor decay time.
The readout time is approximately given by:t R  N x  N y t sr  t v   N x  t i 

(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
A subsection of the CCD (number of horizontal pixels must be divisible by 4) can be readout at full resolution, sometimes dramatically increasing the readout rate while retaining
the highest resolution in the region of interest (ROI). To approximate the readout rate of
an ROI, in Equation 2 substitute the x and y dimensions of the ROI in place of thedimensions of the full CCD. Some overhead time, however, is required to read out anddiscard the unwanted pixels.
The readout rate in frames per second for the PI-MAX3:e2v CCD30-11 1024 × 256 full
frame array running at 2 MHz is shown in Table 2.
Region of Interest Size
Binning1024 x 256

1x1

6.67

1 x 256

270

1 x 101024 x 10*1024 x 1*

1567

1x1

1831

* CCD format using Custom Chip mode
Table 2. Spectral Rates for e2v CCD30-11 Array at 2 MHz

PI-MAX®3 System Manual

56

Version 1.D

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 by entering a value in the Group
fields: for example, a “2” in each of the Group fields will set up 2 x 2 hardware binning.
In LightField, hardware binning is set up via the Region of Interest expander: first byverifying that hardware binning is selected on the Advanced flyout pane, then selecting
Full Sensor Binned, and entering a “2” in fields or by clicking on the Edit ROIs…
button and creating a custom ROI with Bin W and the Bin H values of “2”.
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Possible data loss if the total charge binned together exceeds the capacity of theshift register or output node.

For dual port operation, there are symmetry requirements that limit the choice ofpatterns. Regions of interest (ROIs) must be symmetrical about the center line
(horizontal).

The number of pixels in the serial (horizontal) direction must be evenly divisible
by 4, even after binning.

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, suchas signals with a large fluorescence. Ideally, one would like to bin many pixels toincrease the S/N ratio of the weak peaks but this cannot be done because the fluorescencewould 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 postprocessing binning is accomplished in software, producing a result that represents many
more photons than was possible using hardware binning.

Chapter 5General Operation Factors

57

CCD Type and Readout Port(s)The PI-MAX3 will either have a full frame or an interline CCD. Full frame CCDs such as
the 1024x256 device have a single port for readout. The 1024x1024 interline CCD is
designed for either dual or single port readout. When single port readout is active, theport used has been set at the factory.
Dual port readout is about two times faster than single port readout and occurs whenever
the full frame is being read out or when an ROI is symmetrical about the horizontal
center of the CCD. In WinX, a single port readout will automatically occur when an ROI
is not symmetrical about the horizontal center of the CCD; in LightField, you can either
change the ROI location/size or select single port readout (via the Advanced flyout paneon the Region of Interest expander).
Full Frame Binning
Figure 17 shows an example of 2  2 binning with dual port operation for an interline
array: each pixel of the image displayed by the software represents 4 pixels of the array.
Figure 18 shows the LightField Region of Interest expander setup for full sensor 2  2binning. Figure 19 shows an example of single port operation for a full frame array.

Figure 17. Dual Port Readout: 2 × 2 Binning of Interline CCD

58

PI-MAX®3 System Manual

Version 1.D

Figure 18. Dual Port Readout: LightField Settings for 2 × 2 Binning of Interline CCD

Figure 19. Single Port Readout: 2 × 2 Binning of Full Frame CCD

Chapter 5General Operation Factors

59

WinX and Partial Frame ROI Binning
When setting up a partial frame ROI (regardless of the array type – full frame or interline),
keep in mind that for the PI-MAX3 the following constraint applies: the number of pixels inthe serial (horizontal) direction must be evenly
divisible by 4, even after binning. The software
may refer to the horizontal as X or Wavelength
depending on the application.
Examples: These examples include partial frame
ROIs with and without binning. The terminology isbased on the ROI Setup tab shown to the right.
X Start to End = 200 pixels, no grouping(binning). Since 200/4=50, this is a valid
ROI setup.
X Start to End = 200 pixels and grouping(binning) is by 8. The resulting number ofsuper pixels is 25. Since 25/4=6.25, this is
not a valid ROI setting for the horizontal
direction.

8 is Not Valid
For X Start-Endof 200

X Start to End = 240 pixels, no grouping(binning). Since 240/4=60 this is a valid
ROI setup.
X Start to End = 240 pixels andgrouping (binning) is by 3. The
resulting number of super pixels is
80. Since 80/4=20, this is a valid ROI setup.

Figure 20. Experiment Setup|ROI
Setup tab

X Start to End = 240 pixels and grouping (binning) is by 16. The resulting number ofsuper pixels is 15. Since 15/4=3.75, this is not a valid ROI setting for the horizontal
direction.
LightField and Partial Frame ROI Binning
Partial Frame ROI binning can be defined via the Region of Interest expander’s Custom
Region(s) of Interest function and the Edit Regions of Interest window (Figure 21).
The ROI shown in the image has been created for a PI-MAX3:1024i using dual port
readout. Because the ROI is not centered horizontally, an Experiment Conflict is shown.
If you click on the Experiment Conflict icon , a pop up window will report the natureof the conflict. In this case, the ROI needs to be centered horizontally: you would click on
the middle Center button to reposition the ROI correctly.
Note: Only one ROI can be created when dual port readout is selected. When single port
readout is active (the CCD is a 1024x256 or single port is selected for the 1024x1024
interline), multiple ROIs can be created and the horizontal centering is not required.

60

PI-MAX®3 System Manual

Version 1.D

Figure 21. Edit Regions of Interest window

Figure 22. Partial Frame 2 × 2 Binning for Interline CCD - Single Port Readout (ROI does nothave to be centered horizontally)Chapter 5General Operation Factors

61

Figure 23 shows the LightField Region of Interest expander and 5  3 binning setup for
an interline with dual port readout selected. Both the Full Sensor Binned and theCustom Region(s) of Interest results of using the 5 and 3 bin values are reported.
Note: On LightField’s Region of Interest expander, you can select Full Sensor, Binned
and enter Bin W and Bin H values that would not be allowed if you selected Custom
Region(s) Interest and entered them in the Edit Regions of Interest window. For
example a Bin W=5 and a Bin H=3 would not be allowed via the Edit Regions ofInterest window until you created a horizontally centered ROI whose dimensions would
permit even division by those values. If you use the Full Sensor, Binned function,
LightField creates the appropriately sized ROI and reports the resulting image size. The
Custom Region(s) of Interest panel shows the non-binned ROI size and the bin values
that will be applied to it.

Figure 23. Dual Port Readout: LightField Settings for 5 × 3 Binning for Interline CCD

PI-MAX®3 System Manual

62

Version 1.D

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 binned pixels. Unfortunately, with a highnumber of scans (i.e., above 100), camera 1/f noise may reduce the actual S/N ratio toslightly below this theoretical value. Also, if the light source used is photon flicker (1/fnoise) 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 WinX and LightField software, software binning can either be set up to occur
automatically or as a manual post-processing operation.


WinX: Automatic software binning is set up by entering Group parameters on
the Acquisition|Experiment Setup…|ROI Setup tab card and then selecting
the Use Software Binning checkbox. The drawback to automatic binning is thatthe raw data is lost. Alternatively, you can acquire raw data and then use thepost-processing binning function (located on the Process|Binning andSkipping… dialog) to select the input data, enter the binning parameters, andsave the result to an appropriately named file.

LightField: Automatic software binning is set up by entering the Bin W and
Bin H parameters directly on the Region of Interest expander or when creating a
Custom ROI via the Edit Regions of Interest window. Alternatively you canacquire raw data, load the file in the Data Workspace, select Software Binningfrom the Processes menu, enter the binning parameters, preview the resulting
data, OK the process, and then use the Data Workspace Save function to save theresult to an appropriately named file.

Controller Gain {Analog Gain}
Controller gain (a function of the preamplifier) is software-selectable and is used tochange the relationship between the number of electrons acquired on the CCD and theAnalog-to-Digital Units (ADUs or counts) generated. Selecting the amount of gain isdone on the Acquisition|Experiment Setup…|ADC tab {Analog to Digital
Conversion expander}. The choices are 1 {Low} and 2 {High}.
Three factors should be considered when making the selection: the intensity of theincoming signal, binning, and CCD saturation.
1 {Low}: Users who measure high-level signals may wish to select 1{Low} for
digitization of larger signals: more electrons are required per ADU. Since binningcombines the signal from two or more pixels, the user may also want to select 1{Low} if binning is being applied. In both instances, the goal is to prevent CCD
saturation and maximize signal acquisition.
2 {High}: Users who consistently measure low-level signals may wish to select 2{High}, which requires fewer electrons to generate an ADU and reduces somesources of noise. If saturation occurs at this setting, 1 {Low} should be selected.

Chapter 5General Operation Factors

63

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 16.
Some PI-MAX3 cameras have two complete analog channels including separate A/D
converters. Because the readout noise of CCD arrays increases with the readout rate, it issometimes necessary to trade off readout speed for high dynamic range. The two analog
converters, both high speed, are optimized for slower read rates by digitally processing
the signal in the camera before transferring it to the host.

Logic Out Control
The TTL-compatible logic level output (0 to+3.3 V) from the LOGIC OUT connector on
the rear panel can be used to monitor camera
status and control external devices. By
default, the logic output level is high while
the action is occurring. The timing of thelevel changes depends on the output typeselected on the
Setup|Hardware|Controller/Camera tab{Trigger expander}:

Acquiring{Acquiring}: After a startacquisition command, this output
changes state on completion of thearray cleaning cycles that precede thefirst exposure. Initially low, it goeshigh to mark the beginning of thefirst exposure. In Focus mode
Figure 24. PI-MAX3 Setup|
operation it remains high until the
Hardware|Controller/Camera tab
system is halted. If a specific numberof frames
have been programmed, it remains high until all have been taken and then returns
low. Figure 25 assumes 3 frames have been programmed.

Image Shift {Shifting Under Mask}: This level is at a logic high while theimage is being shifted under the mask.



Logic 1 {Always High}: The level at the connector is high.



Read Out {Reading Out}: It is at a logic high when CCD is being read;otherwise low.



Shutter {Shutter Open}: This level is at a logic high when the photocathode isgated on (signal is accumulating on the CCD) and can be used to drive an
external electro-mechanical shutter. Contact the factory for more information.



Wait for Trigger {Waiting For Trigger}: This level is at a logic high when thecamera is ready to acquire and is waiting for an external trigger (through the EXTSYNC connector) before exposing the CCD. The level goes low when a trigger isdetected: exposure begins. The Wait for Trigger (WFT) signal goes highimmediately after readout or after preopen (if it is active). If continuous cleans isenabled, the camera will check for a trigger at the EXT SYNC connector before

PI-MAX®3 System Manual

64

Version 1.D

entering a continuous clean cycle. If none has occurred, a cleaning cycle isinitiated and completed. Before the next cycle begins, the EXT SYNC connector
is checked again, and exposure will start if a trigger has occurred.
When the Invert LOGIC {Invert Output Signal} check box is checked, the output is at
a logic low when the action is occurring.

Figure 25. Comparison of Shutter {Shutter Open}, Read Out {Reading Out}, and Acquiring{Acquiring} Levels

WinX Experiment Setup
Main tab
In WinX, the first experiment setup parameters are
typically selected/entered on the Experiment
Setup|Main tab. These parameters determine suchthings as 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, and the intensifier mode. The Main parameters aredescribed briefly below.
Number of Images/Spectra and Accumulations
This is the number of sequential frames the software willcollect 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 regionof interest as defined via the ROI Setup tab.
If the Accumulations > 1, each stored frame willcontain summed data sets from two or more exposures.
The number of separate frames stored will the same as
it would be for Accumulations =1, but the total numberof exposures required would be the product of the
Figure 26. Experiment Setup|Main tab
Number of Images/Spectra parameter times the
Accumulations value.
CCD Readout
This parameter selection determines whether the entire CCD array will be used to acquire aframe or if only a rectangular portion (or portions) of the array will be used. When Use Regionof 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.

Chapter 5General Operation Factors

65

Intensifier Gain
The Intensifier gain setting provides continuous adjustment over a range of 1 to 100. Gainis approximately proportional to the number entered. 100 is maximum gain or 100%; 1 isapproximately 1% of maximum gain. The default setting will give good results in many
applications. Gain can only be changed when acquisition is NOT occurring: you must stop
acquisition, change the gain, and then restart acquisition. We suggest beginning with a low
setting and then increasing it until optimum results are obtained.
Note: The intensifier gain also affects the Equivalent Background Illumination (EBI) of
the intensifier. One result of 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 be biased on or off
by the defined pulser gate timing (Gate Mode) or it will be continuously biased off until
Gate mode is selected (Safe Mode).

Timing tab
Experiment setup requires the selection of a variety ofexperiment timing parameters. The parametersdescribed in this section are those that appear on theExperiment Setup|Timing tab (Figure 27). With
the exception of Fast Mode/Safe Mode, which is
described in full, the following paragraphs briefly
describe these timing parameters. The settings
appropriate to the intensifier mode and selected pulser
are discussed in Chapter 7: WinX and Gated
Operation.
Timing Mode
The timing mode parameter refers to the
PI-MAX3's synchronization of data acquisition
with an external TTL signal applied to the
TRIGGER IN connector on the back of the camera
or an internal trigger generated by the internaltiming generator. The modes available depend on
the selected intensifier mode (Safe or Gate) andthe selected pulser (SuperSYNCHRO).

Figure 27. Experiment Setup|Timing
dialog

66

PI-MAX®3 System Manual

Version 1.D

Fast Mode or Safe Mode
In WinX, the Fast Mode or Safe Mode selection determines whether the PI-MAX3 will
run the experiment according to the experiment timing, with no interruptions from thecomputer, or the computer will interrupt the acquisition flow to process each frame as itis received. Figure 28 compares the two modes.
Note: The Safe Mode on the Timing tab is not the same as the Intensifier Safe Mode on
the Main tab.
Fast Mode operation is primarily for collecting “real-time” sequences of experimental
data, where timing is critical and events cannot be missed. Once the PI-MAX3 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 second drawback
is that a data overrun may occur if the number of images collected exceeds the amount ofallocated 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 28, 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 PI-MAX3 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.

Chapter 5General Operation Factors

Figure 28. Safe Mode and Fast Mode Operation

67

PI-MAX®3 System Manual

68

Version 1.D

LightField Experiment Setup
Introduction
Initial experiment setup for LightField is an easy process. If your PI-MAX3 is powered onwhen you start LightField, the camera will be detected and its icon will be placed in the
Available Devices area. When you drag the icon into the Experiment Devices area, theappropriate expanders will be loaded in the Experiment Settings stack. If this is the first time
you have started LightField with this camera, the default settings for the camera will havebeen loaded into the expanders. The following paragraphs provide brief descriptions ofseveral of the Experiment Settings expanders. For detailed descriptions of all of the
expanders, refer to the LightField User’s Manual and LightField’s online help.

Common Acquisition Settings expanderThis expander includes the Number ofFrames, On-CCD Accumulations, andExposures per Frame settings that
determine how many images will beacquired, whether multiple frames will be
used to create a single frame, and whether
multiple exposures will occur while a frame
is being acquired. In addition, this expander
is where the intensifier is enabled and theamount of intensifier gain can be set. The
Advanced flyout allows you to enter a
Phosphor Decay Delay Time and choose
its resolution. Finally, you can specify timestamping information to be stored anddisplayed with the data.

Figure 29. Common Acquisition Settings
expanderChapter 5General Operation Factors

69

Region of Interest expander
The Region of Interest expander allows
you to specify how much of the total sensor
image area will be used to acquire the data
(full sensor or one or more regions ofinterest). This is also where you can set up
and select either hardware or software
binning.
The Advanced button opens a flyout panewhere you the type of binning (hardware orsoftware) to be used if you have entered binvalues other than 1.
The Edit ROIs button opens the Edit
Regions of Interest window where you cancapture a reference image to help you define
which area or areas on the sensor are to be
included when data acquisition is started.
You can draw a selection box to define an areaor you can key values into the ROI fields.

Figure 30. Region of Interest expander

Trigger expander
The Trigger expander is where you specify the trigger source (Internal or External) to
be used to trigger gating. Internal trigger uses the user-selected Internal Trigger
Frequency (selected on the SuperSYNCHRO Timing expander). External requires thatyou define the external trigger so LightField will be able to recognize it when it occurs at
the TRIGGER IN BNC on the rear of the PI-MAX3. This is also where you can choose
the logic level output of the LOGIC OUT BNC.

Figure 31. Trigger expander: Internal

Figure 32. Trigger expander: External

70

PI-MAX®3 System Manual

Version 1.D

SuperSYNCHRO Timing expander
The Super SYNCHRO Timing expander is located at the bottom of the LightField
desktop. This is where you select the type of gating (for example, Repetitive, Sequential,
or DIF) and enter the gate delay and width information. This is also where you can entergate width and delay information for the AUX OUT BNC. When Internal Trigger is theselected Trigger Source or SyncMASTER is turned on, you can also enter the Internal
Trigger Frequency. The hyperlinks open the appropriate expanders so you can check ormake changes to the current settings for the intensifier, trigger, phosphor decay delay,number of frames, on-CCD accumulations, and readout mode. Note that you can grab anddrag the top of the SuperSYNCHRO Timing expander up to show more of the panel ordrag the top down so you can see more of the Experiment Settings stack or theDevice/View panel.

Figure 33. SuperSYNCHRO Timing expanderChapter 6
WinX and Gated Operation
Introduction
This chapter discusses gated operation with the SuperSYNCHRO™ timing generator andaspects of operation of the PI-MAX3 not covered in Chapter 4, First Light. We
additionally suggest that you review Chapter 13, Tips and Tricks, which contains
information that should prove helpful in getting good results in more complex
measurements.
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 fall in a valid gate width during a valid exposure. Manygate pulses can be placed into one exposure at repetitive or sequential 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≤ 4 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-MAX3’s MCP bracketingfeature can be used to extend the On:Off ratio to 106:1.

71

PI-MAX®3 System Manual

72

Version 1.D

Precautionary Measures
WARNING

Intensified CCD detectors, such as the PI-MAX3, 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. If a sustained alarm indication occurs when the controller
is turned on, immediately switch the I.I.T. switch on the back of the PI-MAX3 to the
OFF position. Cover the detector window and only switch the I.I.T. switch to ON after
the illumination level has been lowered to safe operating conditions.

Intensifier Modes and Safety
The Experiment Setup Main screen in WinX applications allows you to select one of two
intensifier modes: Gate Mode or Safe Mode. In Gate Mode, the photocathode is biasedon only for the time that each gate pulse is applied. As a result, the tolerance to room
light is higher in gated operation, but the risk of damaging overload from intense lightsources such as lasers remains. In fact, intense light sources in gated experiments cancause spot damage that would be undetected by the alarm circuit. In Safe Mode, thephotocathode is continuously biased OFF and the intensifier is as safe as it can be.
Note: In order for gating to occur, the I.I.T. switch on the back of the PI-MAX3 mustalso be in the ON position.

Alarm
Note: It is normal for the alarm to sound briefly when the system is turned on.
To reduce the risk of detector damage, the PI-MAX3 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 I.I.T. switch (on the back of the PI-MAX) to the OFF
position. Cover the detector window and only switch the I.I.T. switch to ON after theillumination level has been lowered. If the alarm sounds continuously even when theillumination level is adequately low, shut the system down and contact the factory for
guidance.

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.

Chapter 6

WinX and Gated Operation

73

Timing Mode
When you are in Gate Mode, the internal timing generator will only operate using
Internal Sync timing. This timing mode initiates a readout cycle after each internaltiming generated pulse ensemble.* The handshakes that prevent a readout from occurring
while the timing generator is busy and that prevent the timing generator from pulsing thephotocathode ON while a readout cycle is in progress are performed within the camera.
For this mode, the following parameters are automatically set by the application softwareand cannot be changed: Exposure Time is set to 0, Continuous Cleans is disabled,and Disabled Opened is selected for Shutter Control.
Timing ModeControlled by Internal
Timing Generator“Shutter” Control Ext Trigger Input
Controlled by Internal
Timing Generator

Trigger In BNC

Table 3. Timing Mode, Shutter Control, and Ext. Trigger Input
when using the Internal Timing Generator

Notes:
1. These automatically set parameters may not be visible in some versions of thesoftware.
2. 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-MAX3 tobear on low-light gate-mode experiments. If the experiment allows, many pulses canbe summed on the CCD with no pulse artifacts in the readout. The signal increases
nearly linearly with the number of pulses (within limits imposed by the CCD).

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.

* An internal timing generator pulse ensemble consists of a Gate Start pulse, a Gate Stop pulse,

and one or more Auxiliary pulses.

74

PI-MAX®3 System Manual

Version 1.D

MCP bracket pulsing** keeps the MCP biased OFF except for an interval that brackets
the timing of the photocathode gate as shown in Figure 34. For emitted photoelectrons tobe accelerated in the MCP, the MCP must be biased ON. In conventional intensified
cameras, the MCP is biased ON continuously. In the PI-MAX3, however, when bracket
pulsing is ON, the MCP is biased OFF until just before the photocathode is gated ON andis biased OFF shortly after the photocathode is biased OFF.

Figure 34. Timing: Bracket Pulsing

By bracket pulsing the MCP off (in addition to photocathode gating), the on/off ratio of
the Gen II PI-MAX3 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 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** Bracket pulsing is not available for cameras having a filmless Gen III Intensifier. Gen III

Intensifiers do not respond in the UV.

Chapter 6

WinX and Gated Operation75

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 35 ns delay restriction, these measurements cannot be improved
much by MCP bracket pulsing in the PI-MAX3.
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 adds 10 ns delay to the photocathode gating.
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, thiswill mean inserting an additional delay of 10 ns (min gate delay = 25 ns, with bracket =35 ns) to accomplish coincidence at the detector. MCP bracketing should only be used inexperiments where it is going to make a difference.
Also, MCP bracket gating limits the repetition rate to 6.25 kHz, without it the gate
repetition rate can be up to 1 MHz (more with option boards). This is not a significant
limitation in most cases. Note that with a 10 ns gate at 6.25 kHz, the on/off ratio =16,000, close to the non-bracket value.
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 such measurements,
the option remains of installing an external shutter ahead of the PI-MAX3.

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 slower thanphotocathode gating (35 ns is required to gate the MCP on and another 1 µs 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 35 ns.

PI-MAX®3 System Manual

76

Version 1.D

Setup
MCP Bracket pulse implementation is accomplished by selecting Bracket Pulsing ONfrom the host software. Figure 35, is a timing diagram for bracket pulsing. Insertion delay
between trigger and T0 is ~ 12 ns. Insertion delay to photocathode gate is 35 ns (i.e., theminimum delay in bracket mode is 35 ns): this delay allows the MCP to be up to “fullgain” before the photocathode is gated on.
Note: Because Gen III Intensifiers do not respond in the UV, bracket pulsing is notavailable for these intensifiers.

Figure 35. PI-MAX3 Timing for MCP Bracket Pulsing

Chapter 6

WinX and Gated Operation

77

Additional Experiments
Introduction

Figure 36. Experiments with the PI-MAX3

Figure 36 illustrates the kinds of experiments that can be performed with a PI-MAX3
detector. Of the many gated measurements that can be performed with a PI-MAX3, mostwill 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.
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

78

PI-MAX®3 System Manual

Version 1.D

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. PreTrigger can be helpful if available.
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 Trigger In BNC of the PI-MAX3 (Figure 37). Then perform the steps that follow.

Figure 37. Experiment is Master Clock: Hardware Setup and Timing DiagramChapter 6

WinX and Gated Operation

79

Experiment as Master Clock
The following procedure uses the experiment as the master clock and therefore refers toconnections as shown in Figure 37.
1. Switch on the equipment and start the WinX application software (Ver. 2.5.25 orhigher).
2. Open the Setup|Hardware|Hardware Setup dialog. The screen should resemble
Figure 38, which shows the setup for a KAI 1024x1024 interline camera.

Figure 38. Hardware Setup: Controller/ Camera tab

a. Click on “Load Default Values” on the Cleans/Skips tab.
b. Set the detector temperature by selecting “Detector Temperature” on the Setup
menu, entering the Target Temperature information, clicking on “Set Temp” andthen clicking on “OK”. You may want to refer to the WinView/32 or
WinSpec/32 manual, as appropriate.
3. If you have a spectrograph, set the spectrograph properties by using the menu itemson the “Spectrograph” menu (WinSpec/32 only). If the spectrograph you will beusing has not been installed, first click on “Install/Remove Spectrograph” and do sobefore setting the properties. Figure 39 shows the WinSpec/32 sequence for an
Action 300I spectrograph.

PI-MAX®3 System Manual

801.

Version 1.D

2.

3.

Figure 39. Define Spectrograph and Install/Remove Spectrographs dialogs

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

Figure 40. Move Spectrograph dialog

Chapter 6

WinX and Gated Operation

81

5. At this point, it is a good practice to make sure that the camera is focused by running
it in “Internal Trigger” mode. This requires that you set the experiment parameters on
the Experiment Setup tabs (refer to Figure 41 and Figure 42) and on the
SuperSYNCHRO Trigger tab (Figure 43).
a. On the Experiment Setup|Main tab, choose Gate Mode, and set a value between
0 and 100 for MCP gain.
b. On the Timing tab, select Fast Mode.
c. On the ADC tab, select the appropriate rate.
d. On the ROI Setup tab, select the appropriate ROI.
e. On the SuperSYNCHRO Trigger In tab, select Internal.

Figure 41. Experiment Setup: Main and Timing tabs

Figure 42. Experiment Setup: ADC and ROI Setup tabs

82

PI-MAX®3 System Manual

Version 1.D

Figure 43. SuperSYNCHRO: Trigger tab

6. After setting the parameters and making sure the ambient light level is low, click on
Focus.
7. If the readout mode is currently set to “Use Region of Interest” on the Main tab, thecamera 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 Regionof Interest” before focus mode is activated. Click on “Yes” and the camera will
begin acquiring data.
8. After you make sure that the camera is seeing, stop data acquisition.
9. Set up the pulser (SuperSYNCHRO). The following figures show typical examplesof the screens you would use to set up the SuperSYNCHRO.
a. After selecting the SuperSYNCHRO as the active pulser, click on “Setup
Pulser…”. Define the external trigger on the Trigger In tab. See Figure 44.
b. On the Gating tab, select Sequential as the Active Mode and then click on“Setup…”. If you have a Gen II intensifier, set Bracket Pulsing to OFF for thisexperiment. See Figure 44.

Available for
Gen II Intensifiers

Figure 44. SuperSYNCHRO: Trigger In and Gating tabs

Chapter 6

WinX and Gated Operation

83c. Click on “Setup…” and define the pulse sequence on the Sequential Gating Setup
dialog. See Figure 45.
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, thestart delay is 1 µs and the end delay is 201 µs.)Then select the number of gates per exposure (in this case, 1).

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

Figure 45. Sequential Gating Setup and Width/Delay Sequence dialogs

d. The functions on the Trigger Out tab allow you to enable the SyncMASTER™
trigger output from the SyncMASTER1 and SyncMASTER2 connectors on the
AUX I/O cable and set up the Aux. Out signal at the AUX OUT connector on therear of the PI-MAX3.
When you enable SyncMASTER 1, the output of the SyncMASTER1
connector will be at the frequency entered on the Trigger In tab.

The output of the SyncMASTER2 connector will be at the same frequency
as that of SyncMASTER1. However, you can enter a delay so the edges ofthat signal will occur after the edges of SyncMASTER1.



If you are using the Aux. Out signal from the SuperSYNCHRO to trigger apiece of equipment, then enter the Auxiliary pulse delay time on the Trigger
Out tab (Figure 46). The delay is based on T0 (in effect it is a delay from
SyncMASTER1which also starts at T0). Enter the pulse width needed totrigger the equipment.

PI-MAX®3 System Manual

84

Version 1.D

Figure 46. Trigger Out tabe. Click on OK to program the SuperSYNCHRO.
10. Set up the experiment parameters from the Experiment Setup dialog.
a.

On the Timing tab, change the timing as shown in Figure 47.

b.

On the Main tab, enter the Gain value and switch to Gate Mode. The numberof spectra will be automatically set depending on the number entered on the
Sequential Gating Setup dialog (Figure 45).

Figure 47. Experiment Setup: Timing and Main tabs

Note: In Gate Mode, the photocathode is biased on only for the time that eachgate pulse is applied. This limits the risk of damage resulting from room light.
However, there is a risk of damaging overload from intense light sources such as
lasers.

Chapter 6

WinX and Gated Operation

85

11. After verifying all connections and equipment readiness, click on Acquire to begin
acquiring the spectra (or images).
12. Figure 48 displays the 3-D graph for a “Sequential-Repetitive” experiment with Fixed
Width and Variable Delay (as set in Figure 44 and Figure 45).

Figure 48. Experiment Results in 3-D

86

PI-MAX®3 System Manual

Version 1.D

SyncMASTER1 as Master ClockIf you have a light source that has a “Trigger In”, the PI-MAX3 SyncMASTER function
can be used as the Master clock (cable connections shown in Figure 49). The setup
procedure is much the same as that given for the “Experiment as Master Clock”. The
differences are that Internal Trigger is selected, SyncMASTER is enabled, and a cable isconnected between the PI-MAX3’s AUX I/O cable’s SyncMASTER1 BNC and the lightsource (experiment) for triggering the event.

Figure 49. PI-MAX3 SyncMASTER is Master Clock: Hardware Setup and Timing Diagram

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 4. This
information is important in order to choose the correct length fiber-optic cable.

Chapter 6

WinX and Gated Operation
Delay Source
Photodiode (light -> TTL pulse)
Photodiode -> PI-MAX3 (2 ft BNC cable)
PI-MAX3

Delay
(ns)
2
3
25

87
Total Delay(ns)

Fiber-Optic Cable
Length30

A minimum of 21 ft
of fiber-optic cable isrequired.

Table 4. 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 50. Single Shot: Hardware Setup

After setting up the appropriate hardware, as shown in Figure 50, default values for“Cleans and Skips” are loaded (Figure 51). If the CCD has to wait more than a few
seconds for the external trigger, it is advisable to increase the number of cleans.

Figure 51. Cleans and Skips: Default Values Loaded

88

PI-MAX®3 System Manual

Version 1.D

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 52).

Figure 52. 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).

Figure 53. Repetitive Gating Setup: 100 ns Width, 10 ns Delay

Figure 54 shows the result of the experiment. Figure 55 shows the peak obtained bybinning, in the vertical direction, the entire region around the fluorescence spot.

Chapter 6

WinX and Gated Operation

89

Figure 54. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay

Figure 55. Single Shot Result: Fluorescence Spot, 100 ns Width, 10 ns Delay, Binned Vertically

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.

PI-MAX®3 System Manual

90

Version 1.D

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 Gate Mode would be Repetitive.



The Gate Width and Gate Delay values would be entered in the dialog shown in
Figure 56.

Figure 56. Repetitive Gating Setup dialog.

Chapter 7
LightField and Gated Operation
Introduction
This chapter discusses gated operation with the SuperSYNCHRO™ timing generator andaspects of operation of the PI-MAX3 not covered in Chapter 4, First Light. We
additionally suggest that you review Chapter 13, Tips and Tricks, which contains
information that should prove helpful in getting good results in more complex
measurements.
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 fall in a valid gate width during a valid exposure. Manygate pulses can be placed into one exposure at repetitive or sequential 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≤ 4 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-MAX3’s MCP bracketingfeature can be used to extend the On:Off ratio to 106:1.

91

PI-MAX®3 System Manual

92

Version 1.D

Precautionary Measures
WARNING

Intensified CCD detectors, such as the PI-MAX3, 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. If a sustained alarm indication occurs when the controller
is turned on, immediately switch the I.I.T. switch on the back of the PI-MAX3 to the
OFF position. Cover the detector window and only switch the I.I.T. switch to ON after
the illumination level has been lowered to safe operating conditions.

Intensifier Modes and Safety
In LightField, you can enable or disable the intensifier on the Common Acquisition
Settings expander. When the intensifier is enabled, the camera can be gated; whendisabled, the photocathode is continuously biased OFF and the intensifier is as safe as it
can be.
Note: In order for gating to occur, the I.I.T. switch on the back of the PI-MAX3 mustalso be in the ON position.

Alarm
Note: It is normal for the alarm to sound briefly when the system is turned on.
To reduce the risk of detector damage, the PI-MAX3 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 I.I.T. switch (on the back of the PI-MAX) to the OFF
position. Cover the detector window and only switch the I.I.T. switch to ON after theillumination level has been lowered. If the alarm sounds continuously even when theillumination level is adequately low, shut the system down and contact the factory for
guidance.

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.

Chapter 7

LightField and Gated Operation

93

Timing Mode
When you are in Gate Mode, the internal timing generator will only operate using
Internal Sync timing. This timing mode initiates a readout cycle after each internaltiming generated pulse ensemble.* The handshakes that prevent a readout from occurring
while the timing generator is busy and that prevent the timing generator from pulsing thephotocathode ON while a readout cycle is in progress are performed within the camera.
For this mode, the following parameters are automatically set by the application softwareand cannot be changed: Exposure Time is set to 0, Continuous Cleans is disabled,and Disabled Opened is selected for Shutter Control.
Timing ModeControlled by Internal
Timing Generator“Shutter” Control Ext Trigger Input
Controlled by Internal
Timing Generator

Trigger In BNC

Table 5. Timing Mode, Shutter Control, and Ext. Trigger Input
when using the Internal Timing Generator

Notes:
1. These automatically set parameters may not be visible in some versions of thesoftware.
2. 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-MAX3 tobear on low-light gate-mode experiments. If the experiment allows, many pulses canbe summed on the CCD with no pulse artifacts in the readout. The signal increases
nearly linearly with the number of pulses (within limits imposed by the CCD).

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.

* An internal timing generator pulse ensemble consists of a Gate Start pulse, a Gate Stop pulse,

and one or more Auxiliary pulses.

94

PI-MAX®3 System Manual

Version 1.D

MCP bracket pulsing** keeps the MCP biased OFF except for an interval that brackets
the timing of the photocathode gate as shown in Figure 34. For emitted photoelectrons tobe accelerated in the MCP, the MCP must be biased ON. In conventional intensified
cameras, the MCP is biased ON continuously. In the PI-MAX3, however, when bracket
pulsing is ON, the MCP is biased OFF until just before the photocathode is gated ON andis biased OFF shortly after the photocathode is biased OFF.

Figure 57. Timing: Bracket Pulsing

By bracket pulsing the MCP off (in addition to photocathode gating), the on/off ratio of
the Gen II PI-MAX3 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 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** Bracket pulsing is not available for cameras having a filmless Gen III Intensifier. Gen III

Intensifiers do not respond in the UV.

Chapter 7

LightField and Gated Operation95

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 35 ns delay restriction, these measurements cannot be improved
much by MCP bracket pulsing in the PI-MAX3.
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 adds 10 ns, delay to the photocathode gating.
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, thiswill mean inserting an additional delay of 10 ns (min gate delay = 25 ns, with bracket =35 ns) to accomplish coincidence at the detector. MCP bracketing should only be used inexperiments where it is going to make a difference.
Also, MCP bracket gating limits the repetition rate to 6.25 kHz, without it the gate
repetition rate can be up to 1 MHz (more with option boards). This is not a significant
limitation in most cases. Note that with a 10 ns gate at 6.25 kHz, the on/off ratio =16,000, close to the non-bracket value.
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 such measurements,
the option remains of installing an external shutter ahead of the PI-MAX3.

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 slower thanphotocathode gating (35 ns is required to gate the MCP on and another 1 µs 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 35 ns.

PI-MAX®3 System Manual

96

Version 1.D

Setup
MCP Bracket pulse implementation is accomplished by selecting Bracket Pulsing ONfrom the host software. Figure 35, is a timing diagram for bracket pulsing. Insertion delay
between trigger and T0 is ~ 12 ns. Insertion delay to photocathode gate is 35 ns (i.e., theminimum delay in bracket mode is 35 ns): this delay allows the MCP to be up to “fullgain” before the photocathode is gated on.
Note: Because Gen III Intensifiers do not respond in the UV, bracket pulsing is notavailable for these intensifiers.

Figure 58. PI-MAX3 Timing for MCP Bracket Pulsing

Additional Experiments
Introduction

Figure 59. Experiments with the PI-MAX3

Chapter 7

LightField and Gated Operation

97

Figure 36 illustrates the kinds of experiments that can be performed with a PI-MAX3
detector. Of the many gated measurements that can be performed with a PI-MAX3, mostwill 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.
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. Increasing the Gate Width is useful for trying to findfine detail in a weak decaying signal. If you choose linear, you have to take a lot
more points.

Single Shot: A single shot experiment is one where you have only one chance to catchthe data. Any experiment that cannot 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 sensor runs in Clean Until Trigger mode.
You need to have this active, otherwise dark current would accumulate on the sensor.
When the trigger arrives, the cleans stop, the intensifier gates, 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 Trigger In BNC of the PI-MAX3 (Figure 37). Then perform the steps that follow.

98

PI-MAX®3 System Manual

Version 1.D

Figure 60. Experiment is Master Clock: Hardware Setup and Timing DiagramChapter 7

LightField and Gated Operation

99

Experiment as Master Clock
The following procedure uses the experiment as the master clock and therefore refers toconnections as shown in Figure 60.
1. Switch on the equipment and start the LightField software.
2. Open the Sensor expander and click on the Sensor Cleaning button. The screen
should resemble Figure 61, which shows the setup for the PI-MAX3:1024i camera.

Figure 61. Sensor Cleaning flyout panea. If one or more orange reset buttons are shown on the flyout pane, click on themto reset to the default values.
b. Set the detector temperature by entering the Target Setpoint information.
3. If you have an Acton Series spectrograph, make sure it was turned on when LightField
was started. If you have an LS-785, its icon should be in the Available Devices area.
When the spectrograph icon is dragged into the Experiment Devices area, theSpectrometer expander will be added to the Experiment Settings stack. Set the
spectrograph properties by using the items on the Spectrometer expander.

Figure 62. Spectrometer expander

100

PI-MAX®3 System Manual

Version 1.D

4. Move the grating to the desired wavelength.
5. On the Region of Interest expander, select Full Sensor.

Figure 63. Region of Interest expander: Full Sensor

6. At this point, it is a good practice to make sure that the camera is focused by running it in“Internal Trigger” mode. This requires that you set the experiment parameters on theExperiment Settings expanders, including the SuperSYNCHRO Timing expander.
a. On the Common Acquisition Settings expander, check in the Enable
Intensifier box and set a value between 1 and 100 for the Intensifier Gain.

Figure 64. Common Acquisition Settings expanderb. On the Analog to Digital Conversion expander, select the speed and gain.

Chapter 7

LightField and Gated Operation

101

Figure 65. Analog to Digital Conversion expanderc. On the Trigger expander, select Internal.

Figure 66. Trigger expander: Internal Trigger Source

7. After setting the parameters and making sure the ambient light level is low, click on
the View tab to bring it to the front and then click on the Run button.
8. The camera will begin acquiring data. This data will not be saved.
9. After you make sure that the camera is seeing, stop data acquisition.
10. On the Region of Interest expander, select Full Sensor, Binned and enter 1024 in
the Bin H field.

Figure 67. Region of Interest expander: Full Sensor Binned

11. On the Trigger expander, change the Trigger Source to External and define theexternal trigger.

PI-MAX®3 System Manual

102

Version 1.D

Figure 68. Trigger expander: External Trigger Source

12. Open the SuperSYNCHRO Timing expander (above the Status bar) and begin
setting up the gate timing.
a. Select Sequential as the Active Mode. If you have a Gen II intensifier, set
Bracket Pulsing to OFF for this experiment.
b. Define the pulse sequence.
 Click on the Number of Frames hyperlink and enter the number of frames
to be acquired (in this case, 41).
 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, thestart delay is 1 µs and the end delay is 201 µs.)
 Click on the On-CCD Accumulations hyperlink and enter the number of
On-CCD Accumulations per frame (in this case, 1).
c. The SyncMASTER ON button allows you to enable the SyncMASTER™
trigger output from the SyncMASTER1 and SyncMASTER2 connectors on the
AUX I/O cable and select the frequency for the SyncMASTER outputs. You canalso set up the AUX Output signal at the AUX OUT connector on the rear of the
PI-MAX3.
 When you enable SyncMASTER, the output of the SyncMASTER1
connector will be at the frequency entered on the Internal Trigger
Frequency field.
The output of the SyncMASTER2 connector will be at the same frequency
as that of SyncMASTER1. However, you can enter a delay so the edges ofthat signal will occur after the edges of SyncMASTER1.
If you are using the AUX Output signal from the SuperSYNCHRO to triggera piece of equipment, then enter the Auxiliary pulse delay time. Enter thepulse width needed to trigger the equipment.

Chapter 7

LightField and Gated Operation

Figure 69. SuperSYNCHRO Timing expander

Figure 70. SuperSYNCHRO Timing with SyncMASTER On

103

104

PI-MAX®3 System Manual

Version 1.D

13. After verifying all connections and equipment readiness, contract theSuperSYNCHRO Timing expander, click on the View tab (if it is not in the front),
and click on Acquire to begin acquiring the spectra (or images).
Note: The photocathode is biased on only for the time that each gate pulse is applied.
This limits the risk of damage resulting from room light. However, there is a risk ofdamaging overload from intense light sources such as lasers.

14. Figure 48 displays the graph for a “Sequential-Repetitive” experiment with fixed widthand variable delay. Show Frame Cross Section has been selected. The intensity ofthe selected point was at its maximum in Frame 23.

Figure 71. Experiment Results with Frame Cross Section

Chapter 7

LightField and Gated Operation

105

SyncMASTER1 as Master ClockIf you have a light source that has a “Trigger In”, the PI-MAX3 SyncMASTER function
can be used as the Master clock (cable connections shown in Figure 72). The setup
procedure is much the same as that given for the “Experiment as Master Clock”. The
differences are that Internal Trigger is selected, SyncMASTER is enabled, and a cable isconnected between the PI-MAX3’s AUX I/O cable’s SyncMASTER1 BNC and the lightsource (experiment) for triggering the event.

Figure 72. PI-MAX3 SyncMASTER1 is Master Clock: Hardware Setup and Timing Diagram

106

PI-MAX®3 System Manual

Version 1.D

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
Sensor Cleaning is set to Clean Until Trigger so there is no dark charge accumulation
while 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. This
information is important in order to choose the correct length fiber-optic cable.
Delay Source
Photodiode (light -> TTL pulse)
Photodiode -> PI-MAX3 (2 ft BNC cable)
PI-MAX3

Delay
(ns)
2
3
25

Total Delay(ns)

Fiber-Optic Cable
Length30

A minimum of 21 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 73. Single Shot: Hardware Setup

After setting up the appropriate hardware, as shown in Figure 50, default values for“Cleaning and Skipping” are loaded (Figure 51). If the PI-MAX3 has to wait more than afew seconds for the external trigger, it is advisable to increase the number of cleans.

Chapter 7

LightField and Gated Operation

107

Figure 74. Cleans and Skips: Default Values Loaded

The sequence of operations is similar to the “Sequential” experiments. After focusing thecamera on the fluorescing sample, the appropriate Gain is selected (Figure 52).

Figure 75. 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).

108

PI-MAX®3 System Manual

Version 1.D

Figure 76. Repetitive Gating Setup: 100 ns Width, 25 ns Delay

Figure 54 shows the result of the experiment. Figure 55 shows the peak obtained bybinning, in the vertical direction, the entire region around the fluorescence spot.

Chapter 7

LightField and Gated Operation

109

Figure 77. Single Shot Result: Fluorescence Spot, 100 ns Width, 25 ns Delay

Figure 78. Single Shot Result: Fluorescence Spot, 100 ns Width, 25 ns Delay, Binned VerticallyPI-MAX®3 System Manual

110

Version 1.D

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 Gate Mode would be Repetitive.



The Gate Width and Gate Delay values would be entered in the SuperSYNCHRO
Timing expander (Figure 79).

Figure 79. SuperSYNCHRO Timing expander: Repetitive Gating Setup

Chapter 8
Timing Generator Pulses and Sequences
Pulse Set
Description
A pulse set includes the following signals: MCP_GATE, START, STOP, AUX1, and
SyncMASTER. START and STOP define the photocathode gate pulse. See Figure 80.
Note: MCP GATE, START, and STOP are not visible to the user and are included for
information purposes only.

Figure 80. Pulse Set

The EXPOSE signal remains high for the duration of the pulse set and goes low upon
approximately 15 ns after pulse completion.

Supported Timing Generator Trigger Modes:
Trigger per Pulse: The pulse set is initiated by its own trigger (either internal orexternal). See Figure 81.
Supported Trigger Sources are:

Source 1: Timing Generator internal trigger. A pulse set is initiated by the timing
generator’s internal trigger.



Source 2: External Trigger (on TRIGGER IN BNC). A pulse set is initiated by an
external trigger.

Figure 81. Trigger per Pulse

111

PI-MAX®3 System Manual

112

Version 1.D

Single Sequence
A sequence is the repetition of one pulse set “X” number of times. Figure 82 shows asequence with the pulse set repeated three (3) times.

Figure 82. Sequence with 3 Repetitions

The EXPOSE signal remains high for the duration of the sequence and goes low
approximately 15 ns after sequence completion.

Supported Timing Generator Trigger Modes:
Trigger per Pulse: Each pulse of the single sequence is initiated by its own trigger (alltriggers must be from the same source and all must be either internal or external). See
Figure 83.
Supported Trigger Sources:

Source 1: Timing Generator internal trigger. Each pulse set of the sequenceis initiated by the timing generator’s internal trigger.



Source 2: External Trigger (on TRIGGER IN BNC). Each pulse set isinitiated by an external trigger.

Figure 83. Timing Diagram: Sequence with 3 Repetitions and Trigger per Pulse

Chapter 8

Timing Generator Pulses and Sequences

113

Time Stamping
Time Stamping provides the ability to include the following timing data with each frameof acquired data: Exposure Started;This time stamp indicates the time control is passed from the camera FPGA tothe timing generator, not the actual image intensifier gate time.
Once control is passed to the timing generator, the timing generator waits for a
trigger or triggers (internal or external, as configured by the user.) The timing
generator then executes the timing the user has selected.
When the timing generator completes its task(s), control is then returned to thecamera FPGA.
Exposure Ended.
This time stamp indicates the time when the timing generator returns control tothe camera FPGA.

The resolution for PI-MAX3 time stamps is 1 S.

114

PI-MAX®3 System ManualThis page intentionally left blank.

Version 1.D

Chapter 9
WinX and Dual Image Feature (DIF)
Introduction
The purpose of PI-MAX3 DIF is to acquire a pair of gated images in rapid succession.
The time between frames can be as short as 2 µs (limit imposed by P46 phosphor decaytime) with exposure times as short as 5 ns. The DIF capability is ideally suited tocapturing rapidly evolving events. These experiments will fall into one of two broadly
applicable categories: single trigger and dual trigger experiments. Single trigger
experiments involve a single impulse event that evolves 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 PI-MAX3 must use an interline CCD. In addition, it is recommended that theintensifier have a fast decay phosphor (P46). Since DIF operation involves acquiring
images in rapid succession, phosphor persistence can become the limiting factor in therate of image acquisition.
WinView or WinSpec software (version 2.5.26 or higher) can control the DIF
functionality of the PI-MAX3 and provide full access to the two DIF timing modes:
single trigger and dual 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
soon as the first image is acquired, it is shifted under the masked area and held. The
second exposure begins and is held in the active area until the first image is read out.

115

PI-MAX®3 System Manual

116

Version 1.D

Timing Modes
The following two DIF timing/readout modes are available in WinX:
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 connected to the PI-MAX3 or the
PI-MAX3 can generate the trigger(s) internally. In WinX, DIF readout is selected on the
Hardware Setup|Controller/Camera tab. The timing mode (single or dual trigger) is
selected on the Acquisition|Experiment Setup…|Timing tab.

Setting Up a Single Trigger DIF ExperimentHardwareFigure 84. System Diagram: DIF Operation

Software
For the purposes of this setup, it is assumed that you are using either WinView or
WinSpec to control the system.

Operation
The operation of the PI-MAX3 in DIF mode is similar to the standard operation of a
PI-MAX3 with SuperSYNCHRO. There are only a few differences due to the special
timing modes of DIF, and they will be outlined here.

Chapter 9

WinX and Dual Image Feature (DIF)

117

Figure 85. DIF Operation: Single Trigger Timing Diagram

1. The first requirement is that the PI-MAX3
camera be aligned and focused on the area ofinterest in the experiment. This is best
accomplished while the PI-MAX3 is operatingin Interline mode (i.e., before switching to DIFmode). Verify that the Phosphor Decay
Time is appropriate to the phosphor used byyour camera: (this field is located on the
Setup|Hardware Setup|Controller/Cameratab). The procedure for initial focus is outlined
in Chapter 4.
2. After the alignment and focus, the PI-MAX3
system needs to be put into DIF mode. On
the Setup|Hardware
Setup|Controller/Camera tab, select Dual
Image Feature as the Readout Mode, andthen click OK.

Figure 86. Hardware
Setup|Controller/Camera tab

3. The PI-MAX3 must be set to Gate
Mode for the intensifier to operateproperly. Either click on the Gate
mode button on the Custom
Toolbar or select Gate Mode on
the Acquisition| Experiment
Setup…|Main tab.
4. On the Acquisition|
Experiment Setup…| Timing
tab, verify that Single Trig.
Mode is the selected timing
mode. Continuous Cleans is
recommended for DIF.
5. Select Pulsers from the Setup
menu, select SuperSYNCHRO,

Figure 87. Experiment Setup|Main and Timing tab

PI-MAX®3 System Manual

118

Version 1.D

and click on the Setup Pulser
button.
a. On the Gating tab of theSuperSYNCHRO dialog,
select DIF Gating and clickon the Setup button.
b. On the DIF Gating Setup
dialog, enter the gate widthand delay times.
When entering the Initial
Gate Delay time, makesure that it is ≥ 75 µs.

When entering the InterPulse Gate Delay time,
make sure that the delayis ≥ Phosphor Decay
Time (as entered on the
Setup|Hardware
Setup|Controller/
Camera tab).

c. On the Trigger In tab, selectInternal or External
triggering. If you will beusing External triggering,
make sure the trigger
characteristics match theactive trigger edge, etc. of thetrigger pulse that will be
used.

Figure 88. Pulsers dialog

Figure 89. Gating tab

Figure 90. DIF Gating Setup dialog – Single Trigger

Chapter 9

WinX and Dual Image Feature (DIF)

119

d. If required, on the Trigger Out tab, set up output triggers.
e. At the bottom of the SuperSYNCHRO dialog, click OK to download the gating
sequence to the SuperSYNCHRO.

Figure 91. Trigger In and Trigger Out tabs

6. When the experiment is ready, click on the ACQ button or select Acquire on the
Acquisition menu to start the image acquisition.

Setting Up a Dual Trigger DIF ExperimentHardwareFigure 92. System Diagram: DIF Operation

Software
For the purposes of this setup, it is assumed that you are using either WinView or
WinSpec to control the system.

Operation
The operation of the PI-MAX3 in DIF mode is similar to the standard operation of a
PI-MAX3 with SuperSYNCHRO. There are only a few differences due to the special
timing modes of DIF, and they will be outlined here.

120

PI-MAX®3 System Manual

Version 1.D

Figure 93. DIF Operation: Dual Trigger Timing Diagram

1. The first requirement is that the PI-MAX3
camera be aligned and focused on the areaof interest in the experiment. This is best
accomplished while the PI-MAX3 isoperating in Interline mode (i.e., before
switching to DIF mode). Verify that the
Phosphor Decay Time is appropriate to
the phosphor used by your camera: (thisfield is located on the Setup| Hardware
Setup|Controller/ Camera tab). The
procedure for initial focus is outlined in
Chapter 4.
2. After the alignment and focus, the
PI-MAX3 system needs to be put into DIF
mode. On the Setup|Hardware
Setup|Controller/Camera tab, selectDual Image Feature as the Readout
Mode, and then click OK.

Figure 94. Hardware
Setup|Controller/Camera tab

Chapter 9

WinX and Dual Image Feature (DIF)

121

3. The PI-MAX3 must be set toGate Mode for the intensifier tooperate properly. Either click on
the Gate mode button on the
Custom Toolbar or select Gate
Mode on the
Acquisition|Experiment
Setup…|Main tab.
4. On the Acquisition|
Experiment Setup…| Timing
tab, verify that Dual Trig.
Mode is the selected timing
mode. Continuous Cleans is
recommended for DIF.
5. Select Pulsers from the Setup
menu, select SuperSYNCHRO,
and click on the Setup Pulser
button.

Figure 95. Experiment Setup|Main and Timing tabsa. On the Gating tab of theSuperSYNCHRO dialog,
select DIF Gating and clickon the Setup button.
b. On the DIF Gating Setup
dialog, enter the gate widthand delay times. Whenentering the Pulse 1 Gate
Delay time, make sure that itis ≥ 75 µs.
c. On the Trigger In tab, selectInternal or External
triggering. If you will beusing External triggering,
make sure the trigger
characteristics match theactive trigger edge, etc. ofthe trigger pulse that will be
used.

Figure 96. Pulsers dialog

Figure 97. Gating tab

d. If required, on the Trigger
Out tab, set up output
triggers.
e. At the bottom of theSuperSYNCHRO dialog,
click OK to download thegating sequence to theSuperSYNCHRO.

Figure 98. DIF Gating Setup dialog – Dual Trigger

PI-MAX®3 System Manual

122

Version 1.D

Figure 99. Trigger In and Trigger Out tabs

6. When the experiment is ready, click on the ACQ button or select Acquire on the
Acquisition menu to start the image acquisition.

Tips and Tricks
Experiments using the DIF feature of the PI-MAX3 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-MAX3 has a MONITOR BNC on the back of the camera which is very useful forseeing when the two image exposures occur during the course of the experiment. The
use of the MONITOR BNC and an oscilloscope is discussed in more detail in
Chapter 13: General Tips and Tricks.

The short time between the two images in DIF requires an intensifier with a fast
phosphor. P46 phosphor has a decay time of ~ 2 µs which means it takes 2 µs for thephosphor 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 first image on thephosphor screen. It is usually possible to subtract a percentage of the first image fromthe second image to remove the residual image. If this is not possible, there areintensifiers with P47 phosphor, which is an order of magnitude faster than P46.

The software uses the Phosphor Decay Time to determine how long to wait after thegate 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 Phosphor Decay Time to allow the phosphor more time to decay
before shifting the image. If residual image is not an issue, then Phosphor Decay
Time can be shortened to decrease the time between the two DIF images.

Chapter 10
LightField and Dual Image Feature (DIF)
Introduction
The purpose of PI-MAX3 DIF is to acquire a pair of gated images in rapid succession.
The time between frames can be as short as 450 ns: the second image will have someremnants from the first image due to the longer persistence of the P46 phosphor.
Exposure times can be as short as 2.5 ns. The DIF capability is ideally suited to capturing
rapidly evolving events. These experiments will fall into one of two broadly applicable
categories: single trigger and dual trigger experiments. Single trigger experiments involvea single impulse event that evolves over time such as a laser-induced plasma or
luminescence decay. Dual trigger experiments involve two impulses separated in timesuch as double laser pulse velocimetry measurements.

Requirements
For DIF operation, the PI-MAX3 must use an interline CCD and DIF must be theselected Readout Mode (Readout expander, see Figure 100). The number of frames must
be a multiple of 2 and is set via the Common Acquisitions Settings expander (Figure101). In addition, it is recommended that the intensifier have a fast decay phosphor (P46).
Since DIF operation involves acquiring images in rapid succession, phosphor persistence
can become the limiting factor in the rate of image acquisition.

Figure 100. Readout expander

123

PI-MAX®3 System Manual

124

Version 1.D

Figure 101. Common Acquisition Settings expanderNote: The PI-MAX3:1024i is currently the only PI-MAX3 that can operate in DIF mode.

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
soon as the first image is acquired, it is shifted under the masked area and held. The
second exposure begins and is held in the active area until the first image is read out.

Trigger Setup
Introduction
Triggering for DIF operation is set up on the Trigger and the SuperSYNCHRO
expanders. Trigger setup consists of selecting the trigger response and the trigger source.

Trigger Response
The selected Trigger Response (Readout Per Trigger or Shift Per Trigger) determines
whether one or two triggers will be required for the acquisition. The trigger(s) can either
be internally generated by the PI-MAX3 or can be generated by an external source
connected to the TRIGGER IN connector on the rear of the camera.
Trigger Responses:


Readout Per Trigger: Two shot, one trigger for both shots.



Shift Per Trigger: Two shot, each shot requires a trigger.

Chapter 10

LightField and Dual Image Feature (DIF)

125

Figure 102. Trigger expander

Trigger Source
The trigger source is selectable via the Trigger Source drop-down list. The trigger source
can either be internal or external and is selected/configured on the Trigger expander(Figure 102). In addition, trigger frequency (if internal is selected) is set via theSuperSYNCHRO expander (Figure 103).
Internal: Trigger pulses will be generated by the PI-MAX3 based on the Internal
Trigger Frequency setting (entered on the SuperSYNCHRO Timing expander).
The range of settings is 2 Hz to 1MHz, in 1 Hz increments. Note that the Internal
Trigger Frequency setting also determines the frequency of SynchMASTER1 and
SyncMASTER2 outputs.

Figure 103. SuperSYNCHRO Timing expander: DIF

External: In order for the PI-MAX3 to recognize triggers from an externalsource, you will need to enter the characteristics of the triggers to be used intriggering DIF acquisition. These characteristics include trigger threshold,coupling, termination, and polarity and are entered on the Trigger expander.

PI-MAX®3 System Manual

126

Version 1.D

Setting Up a Single Trigger DIF ExperimentHardware Setup

Figure 104. DIF Hardware Connection diagram

Software Setup and Operation
The operation of the PI-MAX3 in DIF mode is similar to the standard operation of a
PI-MAX3 with SuperSYNCHRO. There are only a few differences due to the special
timing modes of DIF, and they will be outlined here.

Figure 105. DIF Single Trigger Mode Timing diagram

1. The first requirement is that the PI-MAX3 camera be aligned and focused on the areaof interest in the experiment. This is best accomplished while the PI-MAX3 isoperating in Full Frame readout mode (i.e., before switching to DIF mode on the
Readout expander). Verify that the Phosphor Decay Delay is appropriate to thephosphor used by your camera: the phosphor decay delay time entered in LightField
can be viewed or changed after clicking on the Advanced button on the Common
Acquisition Settings expander.

Chapter 10

LightField and Dual Image Feature (DIF)

127

Note: The Phosphor Decay Delay setting is used to tell LightField how long to wait
after the gate pulse to shift the image. If there is some residual image from the first
frame in the second frame, simply increase the Phosphor Decay Delay setting toallow more time for the phosphor emission to decay before shifting the image. If
residual image is not an issue, then the Phosphor Decay Delay setting can be
decreased to reduce the time between the two DIF images.
2. After the alignment and focus, the PI-MAX3 system needs to be put into DIF mode.
On the Readout expander, select DIF as the Readout Mode.

On the Common Acquisition Settings expander, set the Number of Frames toa multiple of 2 (for example 2, 4, 6).

3. On the Trigger expander, verify that Readout Per Trigger is the trigger response.
4. On the Trigger expander, select Internal or External triggering.


For External triggering, make sure the trigger characteristics on the Trigger
expander match the active trigger edge, etc. of the trigger pulse that will be used.



For Internal triggering, set the Internal Trigger Frequency on the
SuperSYNCHRO Timing expander

5. Open the SuperSYNCHRO Timing expander (at the bottom of the window) andbegin entering the internal trigger frequency, gate width, gate delay, Aux output
delay, Aux output width, and the SyncMASTER state (On or OFF).
a. Use the hyperlinks at the top of the expanded panel to make any changes to theintensifier settings, trigger settings, phosphor decay delay time, number of frames(a multiple of 2), and readout mode (DIF or Full Frame).
b. If you are using PI-MAX3 generated internal triggers for DIF acquisition, enter
the internal trigger frequency.
c. Enter the gate width and delay times for the first and second image.


The Initial Gate Delay time will be ≥ 85 µs.

The Second Gate Delay time will be ≥ .441 µs.

d. If required, set up AUX Output trigger.
e. If you want to have trigger output from the SyncMASTER1 and SyncMASTER2
connectors on the AUX I/O cable, click on the SyncMASTER ON button. Whenyou enable SyncMASTER, the output of the SyncMASTER1 connector will be at
the Internal Trigger Frequency. The SyncMASTER2 output will be at the same
frequency but can be delayed (range for delay is from 0 to 999700 ns, inincrements of 100 ns).
6. Verify that the I.I.T. Power switch on the rear of the PI-MAX3 is turned ON and that
Enable Intensifier has been checked on the Common Acquisition Settings expander.
7. When the experiment is ready, click on the Acquire button.

PI-MAX®3 System Manual

128

Version 1.D

Setting Up a Dual Trigger DIF ExperimentHardware Setup

Figure 106. DIF Hardware Connection diagram

Software Setup and Operation
The operation of the PI-MAX3 in DIF mode is similar to the standard operation of a
PI-MAX3 with SuperSYNCHRO. There are only a few differences due to the special
timing modes of DIF, and they will be outlined here.

Figure 107. DIF Dual Trigger Mode Timing diagram

1. The first requirement is that the PI-MAX3 camera be aligned and focused on the areaof interest in the experiment. This is best accomplished while the PI-MAX3 isoperating in Full Frame readout mode (i.e., before switching to DIF mode). Verify
that the Phosphor Decay Delay is appropriate to the phosphor used by your camera:
the phosphor decay delay time entered in LightField can be viewed or changed after
clicking on the Advanced button on the Common Acquisition Settings expander.

Chapter 10

LightField and Dual Image Feature (DIF)

129

Note: The Phosphor Decay Delay setting is used to tell LightField how long to wait
after the gate pulse to shift the image. If there is some residual image from the first
frame in the second frame, simply increase the Phosphor Decay Delay setting toallow more time for the phosphor emission to decay before shifting the image. If
residual image is not an issue, then the Phosphor Decay Delay setting can be
decreased to reduce the time between the two DIF images.
2. After the alignment and focus, the PI-MAX3 system needs to be put into DIF mode.
On the Readout expander, select DIF as the Readout Mode.

On the Common Acquisition Settings expander, set the Number of Frames
to a multiple of 2 (for example 2, 4, 6).

3. On the Trigger expander, verify that Shift Per Trigger is the trigger response.
4. On the Trigger expander, select Internal or External triggering.


For External triggering, make sure the trigger characteristics on the Trigger
expander match the active trigger edge, etc. of the trigger pulse that will be used.



For Internal triggering, set the Internal Trigger Frequency on the
SuperSYNCHRO expander.
5. Open the SuperSYNCHRO Timing expander (at the bottom of the window) andbegin entering the internal trigger frequency, gate width, gate delay, Aux output
delay, Aux output width, and the SyncMASTER state (On or OFF).
6. Use the hyperlinks at the top of the expanded panel to make changes to the intensifier
settings, trigger settings, phosphor decay delay time, number of frames (a multiple of2), and readout mode (DIF or Full Frame).
7. If you are using PI-MAX3 generated internal triggers for DIF acquisition, enter theinternal trigger frequency.
8. Enter the gate width and delay times for the first and second image.


The Initial Gate Delay time will be ≥ 85 µs.

The Second Gate Delay time will be ≥ .441 µs.

If required, set up AUX Output trigger.

If you want to have trigger output from the SyncMASTER1 and SyncMASTER2
connectors on the AUX I/O cable, click on the SyncMASTER ON button. Whenyou enable SyncMASTER, the output of the SyncMASTER1 connector will be at
the Internal Trigger Frequency. The SyncMASTER2 output will be at the same
frequency but can be delayed (range for delay is from 0 to 999700 ns, inincrements of 100 ns).

9. Verify that the I.I.T. Power switch on the rear of the PI-MAX3 is turned ON and that
Enable Intensifier has been checked on the Common Acquisition Settings
expander.
10. When the experiment is ready, click on the Acquire button.

PI-MAX®3 System Manual

130

Version 1.D

Tips and Tricks
Experiments using the DIF feature of the PI-MAX3 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-MAX3 has a MONITOR BNC on the back of the camera which is very
useful for seeing when the two image exposures occur during the course of theexperiment. The use of the MONITOR BNC and an oscilloscope is discussed in
more detail in Chapter 13 - General Tips and Tricks.

The short time between the two images in DIF requires an intensifier with a fast
phosphor. P46 phosphor has a decay time of ~ 2 µs which 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 Phosphor Decay Delay setting to determine how long to
wait after the gate pulse to shift the image. This value can be adjusted in
Advanced flyout pane on the Common Acquisition Settings expander. If there
is some residual image from the first frame in the second frame, simply increase
the Phosphor Decay Delay setting to allow more time for the phosphor emission
to decay before shifting the image. If residual image is not an issue, then the
Phosphor Decay Delay setting can be decreased to reduce the time between the
two DIF images. This setting has no effect on the actual phosphor decay time; itis just used to adjust timing.

Chapter 11
MCP Gating Option
Introduction
MCP gating (not to be confused with MCP bracket pulsing) provides you with a unique
combination of nanosecond-scale gating speed and high ultraviolet QE. Normally, suchhigh UV QE is only available in so-called slow gate intensifiers (i.e., those without anickel underlay). The PI-MAX3 applies the primary gating pulse to the MCP portion of
the tube and applies the bracket pulse to the photocathode. Consequently, it provides thefull 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-MAX3. Insertion delay
between trigger and T0 is ~12 ns. Insertion delay to the photocathode gate is ≥ 30 ns.
Insertion delay to MCP gate is 75-225 ns (dependent on the individual intensifier): this
delay allows the photocathode to be fully on before the MCP is gated. Pulse repetition
rate is limited to 10 kHz.

Setup and Operation
The PI-MAX3 must have an installed MCP Gating board.
1. Make all of the required cable connections for your experiment.
2. Switch on the equipment and start the application software.
3. Set up the gating parameters. You may want to start with a relatively long gate toacquire the phenomenon of interest.
4. Begin running the experiment.
5. Finally, narrow down the gate to the desired operation.
Note: Pulse repetition rate is limited to 10 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.

131

132

PI-MAX®3 System Manual

Version 1.D

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
PI-MAX3. When the laser pulse hits the sample, some atoms are raised to a higher
energy state and then spontaneously relax to the ground state, emitting photons as they doto generate the fluorescence signal. This signal can be applied to a spectrograph thatspreads the fluorescence spectrum across the photocathode of the PI-MAX3. The
spectrum would then be intensified and applied to the PI-MAX3’s CCD array.

Cabling for MCP Gated Operation
Figure 108 illustrates the cabling for an MCP gated experiment using
SuperSYNCHRO™. The laser trigger output is applied to the PI-MAX3’s TRIGGER IN
connector to initiate the timing sequence. SuperSYNCHRO outputs gate the MCP on andoff. To prevent artifacts from the laser from degrading the data, it is essential that
SuperSYNCHRO be inhibited during each readout.

Figure 108. MCP Gated Operation Cabling

Figure 109 is a timing diagram for MCP gating of the photocathode.

Chapter 11

MCP Gating Option

Figure 109. PI-MAX3 Timing in MCP Gated Operation

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

133

134

PI-MAX®3 System ManualThis page intentionally left blank.

Version 1.D

Chapter 12
Picosecond Option
Introduction
The picosecond gating option for the PI-MAX3 allows optical gates down to less than
500 ps (or to the lowest gate width the intensifier will support, whichever is greater). It
consists of a picosecond gating board installed in the PI-MAX3 and some othermodifications to support the board. The picosecond option can operate up to 100 kHz
repetition rate* (the main gate generator goes to 1 MHz) and has a few nanoseconds
larger insertion delay than the main gate generator. The MONITOR BNC output operates
differently in picosecond operation.
* Refer to “Repetition Rate Issues“, on page 136, for detailed information about achievable repetition rates.

Activating Picosecond Operation
WinX: Automatically selects the picosecond gating board whenever the gate width is set
below 3 ns.
LightField: The Picosecond Widths button
will be added to theSuperSYNCHRO Timing expander when a PI-MAX3 containing the picosecond
gating board is detected and loaded as an experiment device.

Gain and Gate Width
The apparent gain of the intensifier falls off as the gate width is reduced. Typically, at thelower limit, the gain is less than 10% of the value observed at 50 ns.
WinX: The software automatically selects the appropriate gate pulse generator to use
when the user selects a gate width: the standard switch-over width is 3 ns.
LightField: The user selects one of the available gate widths from the Picosecond
Widths drop down list and that width will be automatically entered in the Gate
Width field(s).
Note: When Sequential Gating is active, the starting and ending gate widths are thesame: there are NO gate width sequences. However, differing starting and ending gate
delays (swept delay) can be used with a constant gate width.

MONITOR Operation
The MONITOR output (at the BNC on the rear panel) is calibrated to provide a risingedge at the time the optical gate is opening (+/- 500 ps). The MONITOR width is NOT
indicative of the optical gate width. It does NOT change width when the gate width ischanged in the picosecond mode. This is because at these speeds, the electrical pulse
width is not directly translated into optical gate width. In addition, many users do nothave oscilloscopes available that will reliably capture picosecond pulse widths.
Therefore, it was decided to use a pulse width of ~6 ns, regardless of the selected gate
width. The true optical gate width is shown in the application software and this iscalibrated at the factory using a fast pulsed laser.
135

PI-MAX®3 System Manual

136

Version 1.D

Repetition Rate Issues
The picosecond gate generator operates at high peak power levels and therefore has a lower
repetition rate capability than the main gate generator. The normal peak repetition rate for thepicosecond gate generator is 100 kHz. However, it will allow 2 gates to be generated at up to
1 MHz to allow for DIF operation. In addition, the 100 kHz repetition rate cannot besustained continuously. Practically, it must be interrupted periodically to read the CCD so thisis not as great a problem as it may seem. The picosecond gate generator includes a digital
average duty factor limiting circuit that will lock out gating (and light the red LED on the rear
panel) to limit the average heat buildup in the gating circuit. This allows continuous operation
at 10 kHz, and varying numbers of gates per frame at higher rates, depending on the read out
time. Acquisitions of a few frames can usually be done with more gates per frame without
hitting the limit and red light. Some typical numbers for sustained operation with a
PI-MAX3:1024i are shown in Table 7.
Repetition Rate
(kHz)
90
75
50
50
25
10

ADC Rate
(MHz)
16
16
16
16
16
any

Binning & ROI
Full frame
Full frame
Full frame
1Hx100V ROI
Full frame
any

Readout Time
(ms)
~40
~40
~40
~3.4
~40

Gates/Frame
450
461
500
145
666
No limit

Table 7. Typical Picosecond Rates, Readout Times, and Gates/Frame for PI-MAX3:1024i

TimingWhen using optical gate widths from a few nanoseconds to a fraction of a nanosecond,timing is obviously critical. The PI-MAX3 is calibrated with respect to the optical input
plane (front mounting plane) and the rear panel. All other propagation paths must be
accounted for by the user. These are significant, considering a 1 meter coaxial cablerepresents typically 4.5 ns delay or 9 times the gate width, assuming the gate width is set
to 500 ps. To get the best representation of the MONITOR output, the user should use ahigh bandwidth oscilloscope set at 50Ω input impedance. The rise time of the MONITOR
pulse is typically less than 500 ps when terminated in 50Ω.

Methods for Finding a Short Optical Pulse
1. The “textbook” method is to calculate all the delays in the optical and trigger paths
and set the PI-MAX3 delay accordingly. If one does all the arithmetic correctly andhas accurate numbers for all of the delays involved, this method will work. In
practice it seldom works because either some of the delays are not accurately known
or something gets overlooked. The sum of the optical delays must be greater than thetrigger delay (including the PI-MAX3 minimum delay). Doing the sums after the fact
is still a valuable check on the system, even if the timing is achieved by the second
method (see below).
2. A more direct and usually more convenient method is to start with a gate pulse muchwider than the optical pulse and set the PI-MAX3 so the optical gate is wide enoughto be sure it encompasses the optical pulse. This method works well if the pulse isconveniently repetitive, such as one derived from a repetitive laser. Once the pulse isfound, it is an easy matter to reduce the pulse width and adjust the delay until theChapter 12

Sub-Nanosecond Option

137

precise timing needed is achieved. The PI-MAX3 repetitive and sequential gating canbe used to good advantage in this method.
Example:This example is simplified in that it does not address all of the possible settings for
Gate mode setup. It is intended to a sense of how to locate the signal of interest by
successively decreasing gate pulse parameters.
a. Suppose we start with a 1 μs gate and delay set to the minimum value for the
PI-MAX3 (approximately 25 ns), and we see the pulse. We then know the pulse
is arriving between 25 ns and 1.025 μs.
WinXLightField
Gate Mode: Repetitive
Number of Frames: 1
Gate Delay: 25 ns
Gate Width: 1 µs

Number of Images/Spectra: 1b. We now set the sequential gating parameters for 20 ns gate width and 101
images/spectra {frames} at 10 ns per image/spectra {frames}: this spans the 1 μs.
We set the starting gate delay of 25 ns, ending gate delay of 1025, and take thesequence. We can then quickly look through the images or spectra (in WinX or
LightField) and see to the nearest 10 ns when the optical pulse arrived.
WinX

LightField
Gate Mode: Sequential
Number of Frames: 101
Starting Gate Delay: 25 ns
Starting Gate Width: 20 ns
Ending Gate Delay: 1025 ns
Ending Gate Width: 20 ns
Reported Gate Delay Increment: 10 ns

Number of Images/Spectra: 101

c. Assuming we found the signal in the 12th frame, we now set a narrower gate (say3 ns) and sweep about this value in 500 ps steps with a span of 60 ns to find thetime within 500 ps. Adjust the experiment for best signal strength and/or signal
to noise ratio, then jump down to the final gate width (if width < 500 ps isdesired) and again do a sweep to find the exact timing that maximizes the result.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

138

PI-MAX®3 System Manual

Version 1.D

This method has the advantage of assuring that the camera is seeing the pulse
with the most favorable set-up before narrowing the gate width down.
WinX

LightField
Gate Mode: Sequential
Number of Frames: 121
Starting Gate Delay: 116
Starting Gate Width: 3 ns
Ending Gate Delay: 176
Ending Gate Width: 3 ns
Reported Gate Delay Increment: .5 ns

Number of Images/Spectra: 121

Chapter 13
General Tips and Tricks
Introduction
In Chapters 4, 6, and 7, the objective was to show how to take an image or spectrum witha minimal 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-MAX3 can be destroyed if exposed toexcessive light levels. Princeton Instruments cannot take responsibility for damage due tomisuse.
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 I.I.T.
switch (on the back of the PI-MAX3) to the OFF position while you are adjusting theincoming light level. After making adjustments, toggle the switch to the ON position. If
the alarm sounds repetitively, 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.
If you can do so, it is a good idea to avoid intense light on the intensifier even when it isoff. High light levels increase EBI, often for hours, even when the intensifier is off.
Image burn-in can occur with some photocathode types.
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 72.

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-MAX3 and aninternal timing generator, contained a low-jitter pulsed laser triggered from an external
139

PI-MAX®3 System Manual

140

Version 1.D

timer and an external trigger source that is also triggering the pulse generator, a timebudget for this system might appear as follows.
PI-MAX3 Internal Timing Generator
Signal Delay

Cable Delay from External Timer to Laser: 10 ns (6 ft cable is assumed)
Delay (at laser); Trigger to Laser Pulse: 10 ns

Delay; Laser Pulse to Sample: 10 ns
Delay; Fluorescence Signal to Detector: 5 ns
Total Signal Delay: 35 ns

Gate On Delay

Cable Delay from External Timer to PI-MAX3: 15 ns (10 ft cable isassumed)PI-MAX3 Insertion Delay; Trigger to Start of Gate Open Pulse: 25 ns
Total Gate On Delay: 40 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.
Tips: If you have a set of matching probes, use them. Major brand oscilloscope probesof the same model are usually matched to better than 1 ns. If you choose to use coaxial
cables, measure the delay of each and use that information in the calculations.
The PI-MAX3 Monitor BNC connector provides a pulse coincident with respect to theactual intensifier photocathode gating by ± 5 ns. Note that this output is not designed forgood fidelity but rather for accurate timing. The amplitude is typically more than a volt
and we suggest that you monitor the pulse with a high impedance probe (you can also use
50 Ω coaxial cable to a 50 Ω oscilloscope and you will get a lower amplitude pulse).
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

Chapter 13

General Tips and Tricks

141

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.

Adjusting the Signal Delay
The PI-MAX3 internal timing generator gives the user wide latitude with respect toadjusting the delay between the time the timing generator is triggered and the time theGate On and Off edges 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), 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
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.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

142

Version 1.D

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.

Triggered Lasers
Timing Generator as Trigger Source: Using the PI-MAX3’s SyncMASTER1
signal to trigger the laser allows you to get rid of the propagation delay for the External
Trigger (25 ns) and to set up all timing relative to T0. You will still need to consider thedelays from the cable to the laser (1.5 ns/ft), internal delay from trigger to firing (laser
dependent, 50 ns for example), the PI-MAX3's internal minimum allowable gate delay(25 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 Pre-Trigger output that can be used totrigger the Timing Generator, it may not be necessary to use mirrors or fiber-optic cable
to delay the laser pulse. If there is no Pre-Trigger, then taking steps to delay the arrivalof 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.

Chapter 13

General Tips and Tricks

143

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 PI-MAX3, the timing generator is inhibited internally.

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
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/).

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, the3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

144

Version 1.D

experiment 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.
After temperature lock has been established, wait about 5 minutes for the detector
temperature to completely stabilize. Then try taking a few dark charge readings with thedetector operated with the I.I.T. 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 (or > 3000 counts at Gain=2 for somecameras). What you see is not noise. It is a fully subtractable readout pattern. Each CCD
has its own dark charge pattern, unique to that particular device. In addition, a small
offset is built in to prevent noise or pattern from going below zero. Every device has beenthoroughly tested to ensure its compliance with Princeton Instruments' demanding
specifications.

Temperature LockIf the PI-MAX3 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 47.
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 Alarm
CautionContact the factory at once if sporadic or continuous unwarranted alarms occur. They
may indicate intensifier damage or another situation that requires immediate attention.
To reduce the risk of detector damage, PI-MAX3 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 I.I.T. switch on the back of the PI-MAX3 to the OFF
position. Cover the detector window and only switch the I.I.T. switch to ON after theillumination level has been lowered. If the alarm sounds repetitively even when theillumination level is adequately low, select Safe Mode in the WinX application or shutthe system down and contact the factory for guidance.

Chapter 13

General Tips and Tricks

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

145

Chapter 14
System Component Descriptions
Introduction
PI-MAX3 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 Gen II (PI-MAX3 RB, SB, UV) or Filmless Gen III(PI-MAX3 HQ) intensifiers. The operation of the camera system is under complete
control of WinView/32 (Imaging) or WinSpec/32 (Imaging and Spectroscopy) orLightField software packages. In pulsed/gated experiments, where the camera needs to besynchronized to a light source such as laser, the internal timing generator is used.

PI-MAX3 Camera
Mount Adapters
The nose at the front end of the PI-MAX3 camera is designed to accept three types ofmount adapters: C-mount, F-mount, and Spectroscopy-mount. The mount adapter
specified when the system was ordered was installed on PI-MAX3 at the factory (the othertwo mounts are supplied in the PI-MAX3 accessory kit). For more information about thesemount adapters, refer to Appendix E for C- and F-mount adapters and refer toAppendix G for spectroscopy-mount adapters and spectrograph adapters.

Switches, Connectors and Indicators
Power connector: 7-pin D specialty connector;
connects to the PI-MAX3 power supply. See
Figure 110.
AUX OUT: DC-coupled variable delay trigger
output for synchronizing other systemcomponents with the PI-MAX3 internal timing
generator. The host software sets the Delay
Time of this output with respect to the internaltiming generator trigger time. The source
impedance is approximately 100 Ω and it will
provide > 1 V into 50 Ω.
Monitor: BNC port for TTL logic 1 pulse
delayed ± 3 ns with respect to photocathodegating. Cable delay, ~1.5 ns/ft, will be inaddition to the delay at the connector.

Figure 110. PI-MAX3 Rear Panel146

Chapter 14

System Component Descriptions

147

I.I.T. PWR On/Off switch: This switch biases the image intensifier photocathode ON
or OFF. When the I.I.T. switch is set to ON, the photocathode can be gated ON.
Exception: Selecting SAFE on the Experiment Setup Main screen overrides control andwill prevent the photocathode from being biased on regardless of the I.I.T. switch setting.
When the I.I.T. switch is set to OFF, then the photocathode cannot be turned on fromsoftware.

Caution

It is advisable to set the I.I.T. switch to OFF as a fail-safe measure if the PI-MAX3 is left
ON but unused for a period of time.
Error: Red LED lights to warn of excessive repetition rate. Must be off for proper
operation.
Note: Excess Rep Rate LED is also activated by MCP bracket pulsing; MCP bracket
repetition rate limit is 6.25 kHz.
Trigger In: When external triggering is selected in the software, the internal timing
generator will be triggered by an externally derived trigger pulse (range of ±5.5 V)
applied to this input. The threshold, slope, coupling mode (AC or DC), and input
impedance (High or 50 ) are selectable in software. The associated Green LED flashes
each time PI-MAX3 is triggered (glows steadily at high repetition rates).
Note: In gated operation, the green LED indicator flashes each time the PI-MAX3 istriggered. The actual triggering can also be readily determined by observing thesignal at the PI-MAX3 Monitor output with a fast oscilloscope.
Coolant ports: Two standard ¼ size barbed brass fittings for circulating coolant arelocated on the back panel. Either port may be used as the inlet. The coolant cannot
be chilled. Use the Princeton Instruments CoolCUBEII coolant circulator. See“Making the Camera-Circulator Connections,” page 30 and “Temperature
Control,” page 47 for additional information.
Note: Although circulating water will extend the PI-MAX3’s cooling capabilities, it
is not necessary. Most of the PI-MAX3 cooling is provided by the fan.
Ready Out: Level at this BNC is initially LOW. It changes state on completion ofcleaning cycles before the first exposure.
AUX I/O: 26-pin male DB connector. Provides the following five I/O signals (that canbe used to input a trigger to initiate data acquisition, to monitor frame readout
status, and to control an external shutter): T0 Out, Pre-Trigger In, SyncMASTER1,
General Purpose Input 0, and SyncMASTER2. Refer to “AUX I/O Connector
Pinout”, page 161, for more information.
Logic Out: 0 to +3.3V logic level output (TTL-compatible). WinView/WinSpec32(Ver. 2.5.25 or higher) software-selectable Acquiring, Image Shift, Logic 1, Read Out,
Shutter, and Wait for Trigger signal. When the Invert LOGIC check box is checked,
the output is at a logic low when the action is occurring.

Fan: Ventilation fan that runs continuously to remove heat generated by thethermoelectric cooler and the electronics. Air is drawn into the camera through therear grill, picks up the heat from the electronics and the cooler, and is then exhausted
through the side ventilation slots.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

148

Version 1.D

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-25 will generally occur within ten to fifteen 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.
Always turn the power off at the power supply before connecting or disconnecting any

WARNING! cable that interconnects the camera and the computer or serious damage to the CCD may
result. This damage is NOT covered by the manufacturer’s warranty.

Interface Card
GigE Ethernet Card: This card must be installed in the host computer to control the
PI-MAX3 camera and to receive data from the camera.

Extender Bracket Kit
Each PI-MAX3 camera is shipped with an Extender Bracket kit that when mounted
to the rear of the camera, allows the PI-MAX3 to be secured to a laboratory tablewith tapped mounting hole arrays with ¼-20 on 1” spacing or M6 on 25 mm spacing.

CoolCUBEII Coolant Circulator (Option)
Liquid-cooled PI-MAX3 cameras can cool to a lower temperature (typically -35 C)
than air cooling. Instead of using a fan to remove heat, these cameras incorporate aclosed loop system of circulating fluid. The CoolCUBEII circulator unit continuously
pumps the 50:50 mixture of room temperature (23ºC) water and ethylene glycol. To
prevent voiding the warranty, use only the circulator and hoses shipped with yoursystem.

Spectrograph (Option)
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 thespectrograph will be computer-controlled, a suitable interface cable will additionallybe required. For mounting instructions, see Appendix G, Spectrograph Adapters,
beginning on page 186.

Cables
The cables listed below may be supplied with the PI-MAX3 system.
Ethernet Cable: This standard 5 meter (16.4’) cable is a Cat 5e/6 Ethernet cable(6050-0621) for interconnecting the camera and the host computer. The distance between
the camera and the computer can be over 50 meters. Please contact the factory for longer
cables.
AUX I/O Cable: The I/O cable (6050-0660) has a female, DB26, high-density
connector that connects to the AUX I/O connector. The five (5) BNCs at other end of
the cable provide access to the following five I/O signals (that can be used to input atrigger to initiate data acquisition, to monitor frame readout status, and to control anexternal shutter): T0 Out, Pre-Trigger In, SyncMASTER1, General Purpose

Chapter 14

System Component Descriptions

149

Input 0, and SyncMASTER2. Refer to “AUX I/O Connector Pinout”, page 161,
for more information.
Other Cables
Other cables may also be required depending on the system requirements.

TubingClear PVC tubing (3’, 5/32” OD, 1/32” wall McMaster-Carr 5006K42) is suppliedwith the PI-MAX3. This tubing is for connecting the PI-MAX3 to a dry nitrogensource for cooling the photocathode.

Application Software
WinX: The PI-MAX3 camera can be operated by using either WinView/32 or
WinSpec/32, Princeton Instrument's 32-bit Windows® software packages designed
specifically for high-end imaging and spectroscopy, respectively. The Princeton
Instruments' software provides comprehensive image/spectral capture and display
functions. The package also facilitates snap-ins to permit advanced operation. Using theoptional built-in macro record function, you can also create and edit your own macros toautomate a variety of operations.
PVCAM: 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 from thecamera 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 understood that PVCAM issolely 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 commercially available image processing
packages.
Scientific Imaging ToolKit™: SITK™ is a collection of LabVIEW® VIs for scientificcameras and spectrographs. This third party software can be purchased from Princeton
Instruments.
LightField®: The PI-MAX3 can be operated using LightField, Princeton Instrument’s
64-bit Windows Vista® and Windows® 7 compatible software package. LightField
combines complete control over Princeton Instruments’ cameras and spectrometers witheasy-to-use tools for experimental setup, data acquisition and post-processing. LightField
makes data integrity priority #1 via automatic saving to disk, time stamping and retentionof both raw and corrected data with full experimental details saved in each file.
LightField works seamlessly in multi-user facilities, remembering each user’s hardware
and software configurations and tailoring options and features accordingly. The optional,
patent-pending IntelliCal™ package is the highest-performance wavelength calibration
software available, providing up to 10X greater accuracy across the entire focal plane
than competing routines.
PICam™: The standard 64-bit software interface for cooled CCD cameras from
Princeton Instruments. PICam is an ANSI C library of camera control and dataacquisition functions. Currently, the interface supports Windows Vista and Windows 7.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

150

Version 1.D

User Manuals
PI-MAX3 System User Manual: This manual describes how to install and use the
PI-MAX3 system components. The most up-to-date version of this manual and otherPrinceton Instruments manuals can be found and downloaded fromftp://ftp.princetoninstruments.com/public/Manuals/Princeton Instruments/
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.
LightField® User Manual: This manual describes how to install and use theLightField application program (for 64-bit Windows Vista® and Windows® 7 operating
systems). The manual is provided in PDF version on the installation CD and will be
installed in the Princeton Instruments/LightField/Documents subdirectory. Acrobat 7.0
or higher is required. Additional information is available in the program's on-line help.
Note: You can download current versions of Princeton Instruments manuals at
ftp://ftp.princetoninstruments.com/Public/Manuals/Princeton Instruments/. Versionsof Acton manuals are located at
ftp://ftp.princetoninstruments.com/Public/Manuals/Acton/.

Chapter 14

System Component Descriptions

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

151

Chapter 15
Troubleshooting
CAUTION!

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

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 Repetitively

Page 153

Alarm Sounds Sporadically

Page 153

Baseline Signal Suddenly Changes

Page 153

Camera Is Not Responding

Page 153

Camera Stops Working

Page 154

Cooling Troubleshooting

Page 154

Data Loss or Serial Violation

Page 155

Error Occurs at Computer Powerup

Page 155

Ethernet Network is not accessible

Page 155

Excessive Readout NoisePage 157

152

Chapter 15

Troubleshooting

153

Alarm Sounds Repetitively
Immediately reduce the light entering the camera. This can be done by switching I.I.T.
switch on the back of the PI-MAX3 to “OFF” until you lower the source illumination, bydecreasing the lens aperture, or by completely blocking the light into the camera window
with a lens cap or equivalent until the light level has be lowered.
If the alarm sounds repetitively even when the illumination level is adequately low, switch the
I.I.T. to “OFF” and turn off the PI-MAX3 power supply. Then contact the factory: this may
indicate intensifier damage or another situation that requires immediate attention.

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.

Baseline Signal Suddenly Changes by > 1000 ADU
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 CCD enclosure of the camera. If the temperature
setting has not been changed and you observe a baseline signal change, turn off thesystem 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 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 Camera 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
PI-MAX3 power supply OFF. Follow the interface card manufacturer’s installation
instructions and cable the interface card to the “GIG-E” port on the rear of thecamera. Then do a “Custom” installation of WinSpec/32 or WinView/32 with theappropriate interface component selected. 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 “GIG-E” port on
the rear of the camera, close the application program and turn the camera OFF.
Check the cable connections and secure the cables if 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” installation of
WinSpec/32 or WinView/32 with the GigE interface component selected. Be sure todeselect the interface component that does not apply to your system.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

154

Version 1.D

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:
1. Turn off all AC power.
2. Verify that all cables are securely fastened and that all locking screws are in place
and all slide latches are in the latched position.
3. Correct any apparent problems and turn the system on.
4. If the system still does not respond, contact Customer Support.

Cooling Troubleshooting
Temperature Lock Cannot be Achieved or Maintained.
Possible causes for not being able to achieve or maintain lock could include:Ambient temperature greater than +20°C. This condition affects TE-cooled cameras.
If ambient is greater than +20°C, you will need to cool the camera environment orraise the set temperature.



Airflow through the camera and/or circulator is obstructed. The camera needs to haveapproximately two (2) inches (50 mm) clearance around the vented covers. If there isan enclosure involved, the enclosure needs to have unrestricted flow to an open
environment. The camera vents its heat out the side vents near the nose. The air
intake is at the rear of the camera.

A hose is kinked. Unkink the hose.

Coolant level is low. Add 50:50 mix of ethylene glycol and water. Refer tomanufacturer’s instructions for adding coolant.
There may be air in the hoses. Remove air and add 50:50 mix of ethylene glycol andwater. Refer to manufacturer’s instructions for removing excess air and adding coolant.



Circulator pump is not working. If you do not hear the pump running when thecirculator is powered on, turn off the circulator and contact the manufacturer’s
Customer Support.



CoolCUBEII: The circulator is higher than the camera. Reposition the circulator sothat it is 6 inches (150 mm) or more below the camera. The vertical distance should
not exceed 10 feet (3 m). Typically, the camera is at table height and the circulator ison the floor.



The target array temperature is not appropriate for your particular camera and CCD array.



The camera's internal temperature may be too high, such as might occur if theoperating environment is particularly warm, if you are attempting to operate at atemperature colder than the specified limit, or if you have turned off the fan and are
not circulating coolant through the camera. TE cameras are equipped with a thermalprotection switch that shuts the cooler circuits down if the internal temperature
exceeds a preset limit. Typically, camera operation is restored automatically in about
ten minutes. Although the thermo-protection switch will protect the camera, you arenevertheless advised to power down and correct the operating conditions that caused
the thermal-overload to occur.

Chapter 15

Troubleshooting

155

Gradual Deterioration of Cooling Capability
While unlikely with the PI-MA3 camera (guaranteed permanent vacuum for the life of
the camera), if you see a gradual deterioration of the cooling capability, it might due todamaged camera vacuum. This can affect temperature performance such that it may be
impossible to achieve temperature lock at the lowest temperatures. In the kind of
applications for which cooled CCD cameras are so well suited, it is highly desirable tomaintain the system’s lowest temperature performance because lower temperatures resultin lower thermal noise and better the signal-to-noise ratio. Contact the factory to makearrangements for returning the camera to the support facility.

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.

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.
one and reports the address and interrupt assignments for that one as well. In a few

Ethernet Network is not accessible
When the Princeton Instruments software is installed, all Intel Pro/1000 interface card
drivers found on the host computer are updated with the Intel Pro/1000 Grabber Adapter(Vision High-Performance IP Device) driver provided by Pleora Technologies, Inc. If
this computer is connected to an Ethernet network via an Intel Pro/1000 card that does
not use the Pleora driver, the network connection will be broken. The tool used to restore
the network connection depends on whether you are using WinX (32-bit) or LightField(64-bit).

For WinX:
1. Locate the EbDriverTool32.exe file.


Download the EbDriverTool32.exe file to your computer fromftp://ftp.princetoninstruments.com/public/Software/Official/WinX32/GigE/

Or open the default Pleora directory. Typically it is located at C:\Program
Files\Common Files\Pleora. The EbDriverTool32.exe (or EbDriverTool.exe)
file may be in a subdirectory.

2. Run the file.
3. When this program executes, select the appropriate Ethernet card and under the
Action category, choose “Install Manufacturer Driver” from the pulldown menu.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

156

Version 1.D

Figure 111. Ebus Driver Installation Tool dialog

4. After making the selection, click on Install.
5. After the installation you may be asked to reboot the computer. If you are asked toreboot, you can

Click on “Yes” to initiate the reboot.



Click on “No” to wait before rebooting. If you select “No,” you may be required
to close the eBUS Driver Installation Tool dialog. Reboot the computer at yourconvenience.

6. Verify that the network connection has been re-established. If a reboot was required,wait until the reboot has occurred before verifying the connection.

For LightField:
1. Locate the EbDriverTool64.exe file. Typically it is located at C:\Program
Files\Common Files\Pleora. The EbDriverTool64.exe file may be in a
subdirectory.
2. Run the file.
3. When this program executes, select the appropriate Ethernet card and under the
Action category, choose “Install Manufacturer Driver” from the pulldown menu.

Figure 112. Ebus Driver Installation Tool dialog

4. After making the selection, click on Install.
5. After the installation you may be asked to reboot the computer. If you are asked toreboot, you can

Click on “Yes” to initiate the reboot.

Chapter 15

Troubleshooting

157

Click on “No” to wait before rebooting. If you select “No,” you may be required
to close the eBUS Driver Installation Tool dialog. Reboot the computer at yourconvenience.

6. Verify that the network connection has been re-established. If a reboot was required,wait until the reboot has occurred before verifying the connection.

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 1-50 ADU rms (6 -300 ADU pk-pk). This is on topof offset that typically is about 600 counts. Moisture accumulation produces a coarser
noise with many spikes  300 ADU. If these types of spikes occur, especially after thecamera has been in use for an extended period, turn off the system immediately. Have theunit serviced by Princeton Instruments or an authorized service facility of Princeton
Instruments.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

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.

PI-MAX3
1024i

1024x256

CCD type

Kodak KAI:1003 (interline)

e2v CCD30-11 (full frame)

CCD format

1024x1024

1024x256

CCD pixel size

12.8 µm x 12.8 µm

26 µm x 26 µm

Imaging area

13.1 mm x 13.1 mm (18mm dia.)

18 mm x 6.7 mm or
25 mm x 6.7 mm

Intensifier size

18 mm

18 mm or 25 mm

Intensifier type

Gen II, Gen III filmless, or
UNIGEN II

Gen II, Gen III filmless, or
UNIGEN II

Phosphor typeP43, *P46 (optional)

P43, P46 (optional)

Pixel Full Well (min.)130 k eˉ450 k eˉRead Noise (typ.)16 eˉrms @ 4 MHz digitization
30 eˉrms @ 16 MHz digitization
35 eˉrms @ 32 MHz digitization

14 eˉrms @ 500 kHz digitization
15 eˉrms @ 1 MHz digitization
22 eˉrms @ 2 MHz digitization*Contact Princeton Instruments for P46 and P47 phosphor availability.
Table 8. CCD Specifications

Gating:Jitter: ~35 ps RMS
Minimum delay from trigger: ~25 ns (without bracket pulse), ~35ns with bracket
pulse
Delay, width granularity: 10 ps.
Repetition Rate: 1 MHz (“full voltage” pulse), not burst length limit
Maximum Repetition Rate (photocathode)Sustained: 1 MHz in variable mode; 6.25 kHz with bracket
Digital Conversion: 16 bits
Image Intensifier: 18 mm or 25 mm
Method of Coupling: fiber optic
158

Appendix A

Specifications

159

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 is simply secured byfour screws, which require a small Phillips screwdriver. 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.
C-Mount Adapter: Accepts standard C-mount threaded lenses.
Focal Depth (distance from adapter flat to photocathode surface)
Spectroscopy: Mounting face to image plane is factory preset to an opticaldistance of 0.894” ±0.010” [22.71 mm ±0.25 mm].
F-Mount: Mounting face to image plane is factory preset to an optical distance of
1.831” ±0.010” [46.50 mm ±0.25 mm].
C-Mount: Mounting face to image plane is factory preset to an optical distance of
0.690” ±0.010” [17.53 mm ±0.25 mm].
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
Gen II High Res Spatial Resolution
1:1 coupling: typically 45 µm spot size FWHM
Filmless Gen III Spatial Resolution
1:1 coupling: typically 42 µm spot size FWHM
Geometric Distortion: typically < 1 pixel
Sensitivity: Variable intensifier gain adjustment (via software) allows sensitivities from1-80 counts/photoelectron for Gen II and 1-200 counts/photoelectron for Gen III.
Some phosphor choices may result in lower values. Gain adjustment range is 1-100.
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: Linearity is difficult to predict in ICCD systems, especially athigh frame rates. Most intensifiers cannot generate sufficient light in a single
gate to achieve full scale illumination, or even approach it. Generally, it takes a
few milliseconds for an intensifier to recover from a single gate event (if thecharge output is significant). Good linearity is observed when the light intensity
is low and the signal is built up over a large number of exposures or over a longexposure. Poor linearity is observed when one attempts to get large signal
amplitude from a single short exposure. This is a general property of MCP
image intensifiers, not just of PI ICCDs.
* Similar mount for Canon lenses may also be available. Contact factory for information.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

160

Version 1.D

Photocathode Dark Charge (EBI): Red-blue enhanced, < 5 counts/pixel-second;
Red-enhanced, < 15 counts/pixel-second
Phosphor Decay: 3 ms P43 standard, 2 µs
P46 phosphor is optional
Phosphor Emission Spectra
P43 = Gd2O2S:Tb
P46 = Y3Al5O12:Ce
Spectral Range
Gen II: Red-blue enhanced, 180900 nm; Red enhanced, 360-920 nm
Filmless Gen III: HQ, 450-900 nm(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
CCD Cooling: Down to -25°C air cooled; supplementary cooling with circulatingroom-temperature water will enhance cooling performance. Temperatures to-35°C are achievable with supplemental circulating coolant via a CoolCUBEII
circulator. Chilled coolant can achieve even lower temperatures but must be usedwith extreme caution.
Note: See warning in “Temperature Control,” page 47 before initiating
supplemental water cooling.
Readout Noise: 1-1.5 counts RMS in gated operation (100 kHz).
A/D Converters
Standard: 16-bit, 80 MHz readout rate. One or two converters depending on the
CCD
Linearity: better than 1%.
Readout noise: Depends on the pixel rate and CCD type.
Input:
TRIGGER IN: Rear Panel BNC. It is the main trigger input to timing generator.
Used for triggering by an external source. When external triggering is selected in
the software, the internal timing generator will be triggered by an externally derived
trigger pulse (range of ±5.5 V) applied to this input. The threshold , slope, coupling
mode (AC or DC), and input impedance (High or 50 ) are selectable in software.
The associated Green LED flashes each time PI-MAX3 is triggered (glows steadily
at high repetition rates). The actual triggering can also be readily determined byobserving the signal at the Monitor output with a fast oscilloscope.
Outputs:
READY: TTL signal. Represents camera status. It changes state when ready justbefore the exposure.
Gig-E: Gigabit Ethernet connector.

Appendix A

Specifications

161

LOGIC OUT: 0 to +3.3V programmable logic level output (TTL-compatible). The
output can be programmed via software as ACQUIRING, IMAGE SHIFT,LOGIC 1, READ OUT, SHUTTER, or WAIT FOR TRIGGER signal. For
detailed definition of each output, please see “Logic Out Control” (page 63). The
output can also be inverted through software.
AUX Out: DC-coupled programmable delay (delay from T0: 0.01ns - 1 sec) trigger
output to synchronize external devices with PI-MAX3.
Monitor: TTL signal to monitor actual gate timing
AUX I/O: The AUX I/O connector and cable (6050-0660) give you access to the T0
Output, Pre-Trigger Input, SyncMASTER1 Output, General Purpose Input 0, and
SyncMASTER2 Output I/O signals of the AUX I/O connector. The leads on thefive (5) BNC tipped leads are color coded as shown in the table below. Refer to“AUX I/O Connector Pinout” for additional information on these and otheravailable I/O signals.

Name

Color

Pin Center

Pin Return

T0 OUT

Red

Pin 1

Pin 3

PRE-TRIG IN

Green

Pin 2

Pin 6

SyncMASTER1

Blue

Pin 7

Pin 18GP INPUT 0

Gray

Pin 8

Pin 20

SyncMASTER2Black

Pin 23

Pin 25

Table 9. AUX I/O Cable Leads

AUX I/O Connector Pinout

Figure 113. AUX I/O Connector Pinout

The AUX I/O (Input/Output Status) connector provides information about trigger
function, DAC, and TTL signals. Inputs must be at least 2.4 V for a TTL high andless than 0.9 V for a low.
The numbers on the I/O connector diagram correspond to the numbers given to thedefinition of each of the pins. The I/O connector is a female, DB26, high-density
connector. The I/O cable (6050-0660) to access T0 Output (Pin 1), Pre-Trigger Input(Pin 2), SyncMASTER1 Output (Pin 7), General Purpose Input 0 (Pin 8), and
SyncMASTER2 Output (Pin 23) is provided with the PI-MAX3 camera.
PORT #

PIN #3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

SIGNAL Description

PI-MAX®3 System Manual

162
PORT #PIN #Version 1.D

SIGNAL Description

1

T0 Output: LVCMOS FPGA output with limited ESD
protection, goes high at T0. Indicates a trigger has been
received.

2

Pre-Trigger Input: LVCMOS ESD-protected input. PreTrigger is an optional signal that may be used to terminate thecontinuous cleans instruction operation. In ordinary operation
there is a one clean cycle jitter between the trigger and thefinish of cleaning (i.e., the clean cycle in process must becompleted). A rising edge will cause a pre-trigger.
Note: The camera must already be in Acquire mode before thepre-trigger is sent to the input.

3

GND: System chassis ground. Any external circuitry intended
to interface with the trigger control signals must reference thisground connection.

4

Lockout Output: LOW indicates I.I.T. is locked off.

5

(NOT USED)6

GND: System chassis ground. Any external circuitry intended
to interface with the trigger control signals must reference thisground connection.

7

SyncMASTER1 Output: LVCMOS Active high. Userconfigurable output. SyncMASTER1 can be user-configured toprovide a user-specified continuous frequency output (not justwhen the camera is taking data) until halted by the user. In thisconfiguration, the output could be used to synchronize a laser,
shutter, AOTF… with the camera.

8

General Purpose Input 0: Reserved for future use as general
LVCMOS input limited ESD protection.

9

L_Shutter (via 1kOhm): Do Not Use.

10

Source Comp: Future Use. Analog Input.

11

Logic GND: Do Not Use.

12

+5.9 V thru 100 Ohms

13

(NOT USED)

14

General Purpose Output 3 (via 1 kOhm): Reserved

15

General Purpose Output 2 (via 1 kOhm): Reserved

16

General Purpose Output 1 (via 1 kOhm): Reserved

17

SyncMASTER2 Output (via 1 kOhm)

18

GND: System chassis ground. Any external circuitry intended
to interface with the trigger control signals must reference thisground connection.

Table 10. AUX I/O Connector Pinout and Signal Description

Appendix A

Specifications
PORT #PIN #163
SIGNAL Description

19(NOT USED)20

GND: System chassis ground. Any external circuitry intended
to interface with the trigger control signals must reference thisground connection.

21

General Purpose Input 2 (via 1 kOhm): Reserved

22

General Purpose Input 1 (via 1 kOhm): Reserved

23

SyncMASTER2 (via 10 Ohm): Programmable continuous
frequency output (100 ns - 6.55 ms delay from
SyncMASTER1) synchronize external devices with PI-MAX3,
e.g. Q-switch.

24(NOT USED)25

GND: System chassis ground. Any external circuitry intended
to interface with the trigger control signals must reference thisground connection.

26

General Purpose Input 3 (via 1 kOhm): Reserved

Table 7. AUX I/O Connector Pinout and Signal Description (cont.)

Miscellaneous
Dimensions: See Appendix B.
Power Requirements: Nominally 100, 120, 220 or 240 VAC. Refer toFuse/Voltage label on rear of power supply for details. Required DC voltages are
generated in the PI-MAX3 power supply and are supplied via the power cable to
the rear of the camera.
Environmental Requirements:
Storage temperature: -20 C to 55 C
Operating temperature: 5ºC to +30ºC
Relative humidity: <50% noncondensing
TTL Requirements: Rise time  40 ns, Duration  100 ns.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

164

Version 1.D

Internal Pulser
The PI-MAX3 incorporates an internal gate pulse generator and high voltage power
supply controlled by the internal timing generator
Gating Speed
Fast Gate Intensifier
Gen II 18 mm: <5 ns FWHM
Gen II 25 mm: <7 ns FWHM
Filmless Gen III 18 mm: < 5 ns FWHM
Slow Gate 18 mm: ~50 ns FWHM. Contact factory or Princeton Instruments
representative.
Slow Gate 25 mm: ~100 ns FWHM. Contact factory or Princeton Instruments
representative.
Propagation Delay: ≤ 25 ns (35 ns with bracket).
Maximum Repetition Rate (MCP bracket pulsing): 6.25 kHz
MCP Bracket Pulsing: MCP requires 35 ns to gate On and ~1 µs to gate Off.
Note: Bracket pulsing only applies to units having a Gen II Image Intensifier. In
the case of units having a Filmless Gen III Image Intensifier, bracket pulsing
does not apply.

Intensifier Quantum Efficiency
Quantum Efficiency (QE) curves for selected Gen II and Gen III filmless intensifiers:

Appendix A

Specifications

165

Figure 114. Intensifier QE Curves

CoolCUBEII Circulator
Closed loop system
Hoses: Two 3 meter (10’) hoses may be supplied with the PI-MAX3 camera. Thesehoses are made up of a .3 meter (2’) piece of ¼” ID hose joined by a reducer to a
2.4 meter (8’) piece of 3/8” ID hose. Refer to your coolant circulator’s specifications
regarding circulator-compatible hose fittings. If a Princeton Instruments CoolCUBEII
circulator is ordered with the camera, hoses are supplied with appropriate
CoolCUBEII connectors.
Note: Part numbers for the hose, reducer fitting, and CoolCUBEII fitting are
McMaster MCM # 5624K11 (1/4 ID) and #5624K12 (3/8 ID); McMaster #MCM 91355K32 (3/8-1/4 Reducer); and CPC # NS6D17006 (3/8” Quick
Disconnect), respectively.
Coolant: 50:50 ethylene glycol and water at 23°C
Dimensions: Refer to Appendix B, “Outline Drawings”, page 172
Circulator Weight (Filled): 6.0 lbs (2.7 kg)
Hose Weight (Filled): 3.0 lbs (1.4 kg) per hoseComputer
The GigE Ethernet communications interface is used for communication between the
PI-MAX3 camera and the host computer. The minimum computer requirements for thesystem are as listed below:Operating System WinX: Windows® XP (32-bit with SP3 or later), Vista (32-bit), or Windows 7(32-bit) LightField: Vista (64-bit), or Windows 7 (64-bit)
2 GHz Pentium® 4 (or greater)

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

166









Version 1.D

1 GB RAM (or greater)
CD-ROM drive
At least one unused PCI card slot (32-bit) (PCI 2.3 compliant 32-bit 33/66 MHz bus)
Super VGA monitor and graphics card supporting at least 65535 colors with at least
128 Mbyte of memory. Memory requirement is dependent on desired display
resolution.
Hard disk with a minimum of 1 Gbyte available. A complete installation of the
program files takes about 50 Mbytes and the remainder is required for data storage,
depending on the number and size of images/spectra collected. Disk levelcompression programs are not recommended. Drive speed of 10,000 RPM
recommended.
Mouse or other pointing device.

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: < 80%; non-condensing.
±±Appendix A

Specifications

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

167

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

PI-MAX3

Figure 115. Outline Drawing: PI-MAX3 with C-mount Adapter

168

Appendix B

Outline Drawings

Figure 116. Outline Drawing: PI-MAX3 with F-mount Adapter

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

169

170

PI-MAX®3 System Manual

Version 1.D

Figure 117. Outline Drawing: PI-MAX3 with Spectroscopy-mount Adapter

Appendix B

Outline Drawings

PI-MAX3 Power Supply

Figure 118. Outline Drawing: PI-MAX3 Power Supply

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

171

172

PI-MAX®3 System Manual

CoolCUBEII Circulator

Figure 119. Outline Drawing: CoolCUBEII Circulator

Version 1.D

Appendix B

Outline Drawings

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

173

Appendix C
Cross-Referencing of WinX andLightField Terms
WinX-to-LightField
WinX

LightField

Active Rows Parallel to Shift Register

Active Height

Active Shift Register Columns

Active Width

ADC Rate

Speed

ADC Resolution

Bit Depth

Continuous Cleans

Clean Until Trigger

Controller Gain

Analog Gain

Custom Chip

Custom Sensor

Custom Timing

Custom Timing

Disabled Closed (Shutter)

Always Closed (Shutter)

Disabled Open (Shutter)

Always Open (Shutter)

Dual Trigger Mode

Shift Per Trigger

Easy Bin

Sensor Readout Region expander functions

Edge Trigger

Trigger Determined By

External Sync

Readout Per Trigger

F.T. Dummies or Frame Transfer Dummies

Active Area: Top Margin

Focus

Preview or Run

Free Run

No Response

Logic Out

Output Signal

Logic Out: Logic 0

Output Signal: Always Low

Logic Out: Logic 1

Output Signal: Always High

Logic Out: Not Ready

Output Signal: Busy

Logic Out: Not Scan

Output Signal: Not Reading Out

Logic Out: Shutter

Output Signal: Shutter OpenMinimum Block Size

Final Section Height

Normal Shutter

Normal (Shutter)
174

Appendix C

Cross-Referencing of WinX and LightField Terms

WinX

LightField

Number of Blocks

Final Section Count

Number of Cleans

Number of Clean Cycles

Number of Strips per Clean

Clean Cycle Height

Post-Dummy Rows Parallel to Shift Register

Active Area: Bottom Margin

Post-Dummy Shift Register Columns

Active Area: Right Margin

Pre-Dummy Rows Parallel to Shift Register

Active Area: Top Margin

Pre-Dummy Shift Register Columns

Active Area: Left Margin

PreOpen (Shutter)

Open Before Trigger (Shutter)

Readout Port

Quality

Shutter Close Compensation Time

Closing Delay

Shutter Control

Shutter Mode

Shutter Open Compensation Time

Opening Delay

Single Trigger Mode (DIF)

Readout Per Trigger

Skip Serial Register Clean (deselected)

Clean Serial Register

Target Temperature

Temperature Setpoint

Timing Mode

Trigger Response

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

175

176

PI-MAX®3 System Manual

Version 1.D

LightField-to-WinX
LightField

WinX

Active Area: Bottom Margin

Post-Dummy Rows Parallel to Shift Register

Active Area: Left Margin

Pre-Dummy Shift Register Columns

Active Area: Right Margin

Post-Dummy Shift Register Columns

Active Area: Top Margin

F.T. Dummies or Frame Transfer Dummies

Active Area: Top Margin

Pre-Dummy Rows Parallel to Shift Register

Active Height

Active Rows Parallel to Shift Register

Active Width

Active Shift Register Columns

Always Closed (Shutter)

Disabled Closed (Shutter)

Always Open (Shutter)

Disabled Open (Shutter)

Analog Gain

Controller Gain

Bit Depth

ADC Resolution

Clean Cycle Height

Number of Strips per Clean

Clean Serial Register

Skip Serial Register Clean (deselected)

Clean Until Trigger

Continuous Cleans

Closing Delay

Shutter Close Compensation Time

Custom Sensor

Custom Chip

Custom Timing

Custom Timing

Final Section Count

Number of Blocks

Final Section Height

Minimum Block Size

No Response

Free Run

Normal (Shutter)

Normal Shutter

Number of Clean Cycles

Number of Cleans

Open Before Trigger (Shutter)

PreOpen (Shutter)

Opening Delay

Shutter Open Compensation Time

Output Signal

Logic Out

Output Signal: Always High

Logic Out: Logic 1

Output Signal: Always Low

Logic Out: Logic 0

Output Signal: Busy

Logic Out: Not Ready

Output Signal: Not Reading Out

Logic Out: Not Scan

Output Signal: Shutter Open

Logic Out: Shutter

Preview

Focus

Appendix C

Cross-Referencing of WinX and LightField Terms

LightField

WinX

Quality

Readout Port

Readout Per Trigger

External Sync

Readout Per Trigger (DIF)

Single Trigger (DIF)

Sensor Readout Region expander functions

Easy Bin

Shift Per Trigger (DIF)

Dual Trigger Mode (DIF)

Shutter Mode

Shutter Control

Speed

ADC Rate

Temperature Setpoint

Target Temperature

Trigger Determined By

Edge Trigger

Trigger Response

Timing Mode3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

177

Appendix D
Extender Bracket Kit
An Extender Bracket kit is shipped with each PI-MAX3.After securing the bracket at therear of the PI-MAX3, you can mount the PI-MAX3 to any laboratory table with either
25 mm or 1 inch hole spacing.
To secure the plate to the camera:
1. Remove the extender bracket
and the three (3) 6-32x1/4”
flathead screws from the bag.
2. Turn the camera upside down.
3. With the rear of the camera
facing you, place the tongue ofthe bracket into the cutout under
the now topmost edge. The text
on the bracket should be visible.
4. Secure the plate with the threescrews.
5. Turn the camera right side up
and secure it to the laboratory
table. If you will be using one ormore mounting holes at thebottom front of the camera,
tighten the fastener(s) there
before tightening down thefastener(s) at the extenderbracket.
Note: The table mounting holes
in the plate are elongated toallow for tolerance variations.

Figure 120. Extender Bracket Kit mounted to
PI-MAX3

178

Appendix C

Cross-Referencing of WinX and LightField Terms

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

179

Appendix E
Mounting and Focusing C-Mount andF-Mount Lenses
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 121), locate the large indicator dot on theside of the lens. There is a corresponding dot on the front side of the camera lens mount. Lineup the dots and slide the lens into the mount. Then turn the lens counterclockwise until a clickis heard. The click means that the lens is now locked in place.

Figure 121. 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.
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-MAX3 can be mounted at any attitude or angle. The camera can rest on any
secure surface. Take care not to block the ventilation openings.

WARNINGIn 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.

180

Appendix C

Cross-Referencing of WinX and LightField Terms

181

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.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

Appendix F
C-, F-, and Spectroscopy-Mount Adapters
Accessory Kits
PI-MAX3 18 mm Tube
Among the items in the accessory kit shipped with an 18 mm PI-MAX3 are three adapter
kits (C-mount, F-mount, and spectroscopy-mount adapters are supplied, one of which has
been factory-installed on the camera), a double-ended screwdriver with magnet top, and a
PI-MAX3 (with spectroscopy-mount adapter) to Acton spectrograph quick start sheet.

PI-MAX3 25 mm Tube
Among the items in the accessory kit shipped with a 25 mm PI-MAX3 are two adapter
kits (F-mount and spectroscopy-mount adapters are supplied, one of which has beenfactory-installed on the camera), a double-ended screwdriver with magnet top, and a
PI-MAX3 (with spectroscopy-mount adapter) to Acton spectrograph quick start sheet.

Adapter Kits
The table below lists the part numbers for the individual adapter kits that may be shippedin the accessory kit.
Kit

Part Number

Contents

C-Mount Adapter

7389-0031

Adapter, 4-40x 7/16 flat head Phillips
screws, dust cover

F-Mount Adapter

7389-0033

Adapter, 4-40x 7/16 flat head Phillips
screws, dust coverSpectroscopy-Mount Adapter

7389-0032

Adapter, 4-40x7/16 flat head Phillips
screws, dust cover

NVUV Spectroscopy-Mount
Adapter

7389-0039

Adapter, 4-40x7/16 flat head Phillips screws,
o-ring (2.739” I.D.), o-ring (2.614” I.D.), dust
cover

Figure 122. Screwdriver with Reversible Flat and Phillips tips.

182

Appendix F

C-, F-, and Spectroscopy-Mount Adapters

183

PI-MAX3 to Acton Spectrograph Quick Start Guides
Because each PI-MAX3 system is shipped with a spectroscopy-mount adapter kit, aquick start guide for mounting a PI-MAX3 with spectroscopy-mount adapter to an Acton
spectrograph is included. Typically, the guide assumes that there is a spectroscopy-mountadapter mounted to the face of the PI-MAX3 camera.

Standard C-, F-, and Spectroscopy-Mount Adapters
To change from one adapter to another:
1. Using the supplied screwdriver, remove the four (4) Phillips head screws that
secure the adapter to the front of the PI-MAX3.
Note: If the Phillips end of the screwdriver is not available, pull the driver shaft
out of the handle, flip the shaft, and insert the flat end into the handle.
2. Remove the existing adapter and store it in a safe place.
3. Using the same screws, mount the new adapter to the front of the PI-MAX3.

Figure 123. PI-MAX3 Mount Adapters

Spectroscopy-Mount for NVUV Cameras
In addition to the spectroscopy adapter, NVUV cameras require two o-rings, each with adifferent inner diameter (I.D). Typically, the camera would be shipped with the adapter
mounted to the face of the camera and the 2.739” ID o-ring (lightly coated with vacuum
grease) would already be in the groove between the face of the camera and thespectrograph adapter. The 2.614” ID o-ring (lightly coated with vacuum grease) is
installed in the groove on the face of the spectrograph adapter. Figure 124 shows where
the two different o-rings are installed.
To mount an NVUV spectroscopy-mount adapter:
1. Using the supplied screwdriver, remove the four (4) Phillips head screws that
secure the current adapter to the front of the PI-MAX3.
Note: If the Phillips end of the screwdriver is not available, pull the driver shaft
out of the handle, flip the shaft, and insert the flat end into the handle.
2. Remove the existing adapter and store it in a safe place.
3. After lightly applying vacuum grease to the o-rings, position the larger diameter

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

184

PI-MAX®3 System Manual

Version 1.D

ring in the groove on the face of the camera.
4. Using the same screws, mount the spectroscopy-mount adapter to the front of the
PI-MAX3.
5. Position the small diameter ring in the groove on the face of the adapter.
A spare set of o-rings may be supplied. If you need to use one of these spares, be sure tolightly coat it with vacuum grease before putting it in place. Lightly coating the o-rings
with vacuum grease helps to insure air-tight seals between the camera and adapter andbetween the adapter and the spectrograph sliding tube.
O-ring (2.739” ID)in groove

O-ring (2.614” ID)in groove

Figure 124. O-ring Positions for PI-MAX3 NVUV Cameras

Optical Distance from Mounting Face to Image Plane
Each adapter has a preset optical distance from the mounting face to the image plane. The
distance varies from one adapter type to another and is explained on the PI-MAX3
outline drawings. For quick reference, the distances are given below.
C-Mount: Mounting face to image plane is factory preset to an optical distance of
0.690” ±0.010” [17.53 mm ± 0.25 mm].
Spectroscopy: Mounting face to image plane is factory preset to an opticaldistance of 0.894” ±0.010” [22.71 mm ± 0.25 mm].
F-Mount: Mounting face to image plane is factory preset to an optical distance of
1.831” ±0.010” [46.50 mm ± 0.25 mm].

Appendix F

C-, F-, and Spectroscopy-Mount Adapters

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

185

Appendix G
Spectrograph Adapters
Introduction
A PI-MAX3 with the spectroscopy-mount adapter can be readily mounted to an Acton
Series spectrograph or to an IsoPlane SCT-320 spectrograph.. Mounting the camera to an
Acton Series spectrograph requires a male sliding tube that slides into the spectrograph forsetting the focus. Mounting a PI-MAX3 to an IsoPlane is a matter of bolting it directly tothe mounting plant on the IsoPlane.
Notes:
1. When mounted to a spectrograph, the text on the back of the PI-MAX3 should beright side up.
2. A C-mount adapter plate and nut are available for mounting a camera with a C-mountadapter to an Acton Series spectrograph. See “Acton (C-Mount Adapter)” on
page 192 for mounting instructions.

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 SP-2300i spectrograph,
can be easily adapted to other spectrographs. For IsoPlane SCT-320 related focusing
information, see “IsoPlane SCT-320 Spectrograph” on page 188.
Tips:
1. Use a USB-powered or a DC-powered light source. The 60 Hz of an AC-powered
light source may make it more difficult to achieve focus.
2. If you must use an AC light source, set the SuperSYNCHRO Internal frequency toaround 10 Hz.

Acton Series Spectrograph
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 computer, turn the power on, wait
for the spectrograph to initialize.
3. With the PI-MAX3 mounted to the spectrograph and connected to the computer, turnon the power and wait for the detector to initialize.
186

Appendix G

Spectrograph Adapters

187

4. Boot the application software. If you are using WinSpec you will need to define thespectrograph. If you are using LightField, you will need to drag the icons for the PIMAX3 and the spectrograph into the Experiment Devices area.
5. Set the spectrograph to 435.8 nm if using a mercury source or to 0.0 nm if using abroadband 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.
6. Set the slit to 25 µm. If necessary, readjust the SuperSYNCHRO frequency tomaintain optimum (near full-scale) signal intensity.
7. Begin running in Focus or Preview mode.
8. 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 SP-2300i: The
mounting adapter includes a tube that slides inside another tube to move thedetector in or out as required to achieve optimum focus.



Short focal-length spectrographs: there is generally a focusing mechanismon the spectrograph itself which, when adjusted, will move the optics asrequired 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
be to adjust the spectrograph’s focusing mirror or to shim the detector.

9. 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.
Note: With LightField, you can use the Align Spectrometer function.
10. 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).

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

188

Version 1.D

IsoPlane SCT-320 Spectrograph
Because the PI-MAX3 is mounted directly to the mounting plate on the IsoPlane focusing
and alignment is different from the way that focusing and alignment are performed for an
Acton Series spectrograph. The following information assumes that you are familiar withthe locations of the mounting plate, Micrometer Compartment, and the locking set screw.
If not, refer to the IsoPlane manual supplied with the spectrograph.
Notes:
1. When adjusting focus for IsoPlane for the first time with a PI-MAX3, it is likely that
the IsoPlane focus mirror will need to be adjusted. If the IsoPlane was previously
used with a PIXIS or other Princeton Instruments camera with a back focus distanceof approximately 0.6 inches, the focus setting will need to be changed to a much
lower micrometer reading when focusing using a PI-MAX3 since the PI-MAX3 has aback focus distance of approximately 0.9 inches.
2. If the PI-MAX3 has a 25mm intensifier, some vignetting of the sides of the focal
plane is normal. Vignetting is much less likely to occur if the PI-MAX3 has an
18 mm diameter intensifier.
3. If the IsoPlane was ordered with a shutter at the entrance slit and a PI-MAX3 is to be
used with this IsoPlane, the shutter must either be removed from the IsoPlane orcontrolled by an Acton SHC-EXT external shutter control box if one is available. See
the IsoPlane manual for shutter removal instructions.
1. Mount an Acton light source such as the dual HG/NeAr source in front of theentrance slit of the spectrograph.
2. With the spectrograph properly connected to the computer, turn the power on, wait
for the spectrograph to initialize.
3. With the PI-MAX3 mounted to the spectrograph and connected to the computer, turnon the power and wait for the detector to initialize.
4. Boot the application software. If you are using WinSpec you will need to define thespectrograph. If you are using LightField, you will need to drag the icons for the
PI-MAX3 and the spectrograph into the Experiment Devices area.
5. Set the spectrograph to 435.8 nm if using a mercury source or to 0.0 nm if using abroadband source.
6. Remove the cover from the Micrometer Compartment.
7. Using a 3/32” hex wrench, loosen the locking set screw.
8. While continuously acquiring data, adjust the micrometer until you maximize theintensity level of a selected peak or peaks.
9. Tighten down the locking set screw.
10. Place the Micrometer Cover on the spectrograph. Replace and tighten all of the coverscrews.
11. Next adjust the rotation. First, use a 9/64” hex wrench to loosen the four screws at thecorners of the detector mounting plate. While watching a live display of the line,
rotate the detector (up to 4 degrees of rotation are possible). The line will go frombroad to narrow and back to broad. Leave the detector rotation set for the narrowest
achievable line.

Appendix G

Spectrograph Adapters

189

Note: With LightField, you can use the Align Spectrometer function.
12. 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.
13. After completing the rotational alignment, re-tighten the four screws.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

190

Version 1.D

Mounting a PI-MAX3 (3.60 3-hole Slotted Flange) to an Acton
Series SpectrographTools
5/32” Hex wrench
3/32” Hex wrench
5/16” Open end wrench (provided in Spectrometer Kit
bag)(3) 10-32x ½” hex head stainless steel screws (provided inSpectrometer Kit bag)

Procedure
1. Remove shipping plate and store.

2. Remove spacer and store.

3. Loosen setscrew with
3/32” hex wrench.

4. Loosen setscrew.

5. Gently rotate and pull.

6. Finger tighten hex head screws.
Leave about ¼” thread exposed.

Appendix G

Spectrograph Adapters

7. Mount tube to camera, align bafflewith bottom/top of camera, and tighten
mounting screws.

8. Gently rotate while inserting.

9. Tighten setscrew.

10. Tighten setscrew.

191

Note: Adapter parts are machined to provide a tight fit. It may be necessary to rotate the detector backand forth when inserting the sliding tube into the spectrograph. Forcing the tube into the spectrometer
could permanently damage the tube and the spectrometer opening.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

192

Version 1.D

Acton (C-Mount Adapter)

Qty

P/N

Description

1

8401-071-01 Adapter Plate

1

8401-071-02 Threaded C-Mount Adapter

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: Spectrometer parts are machined to provide a tight fit. It is necessary to rotate thedetector back and forth when inserting the sliding tube into the spectrometer. Forcing the tube
into the spectrometer could permanently damage the tube and the spectrometer opening.

Appendix G

Spectrograph Adapters

193

Mounting a PI-MAX3 to an IsoPlane SCT-320

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 mounting
plate on the IsoPlane.
2. Leaving 1/4" of thread exposed, screw the three (3) hex head screws into themounting plate.
3. Mount the detector to the mounting plate: the text should be right-reading on the backof the detector.
4. Tighten the three screws with a 5/16” open end wrench.
Notes:
1. Rotational alignment of the detector to the spectrograph optics is done by loosening
and subsequently retightening the screws at the mounting plate corners. The holes are
slotted to allow about 4° of rotation.
2. If the IsoPlane was ordered with an internal shutter, an external shutter control box
will be required to control the shutter or the shutter will need to be removed. See the
IsoPlane SCT 320 manual for shutter removal instructions.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

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
194

Appendix H

Glossary195

be reduced by cooling the intensifier (or environment) and is usually negligible in
gated applications.
Exposure Time: The period during which the camera allows incoming signal to integrateon 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 Gate Mode, theexposure time is determined by an internal pulse ensemble defined by the internaltiming generator gating setup.
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 but data storage does not begin until the arrival of an
external trigger pulse.
Frame: The area of the CCD array that is readout after an exposure time ends. For a
1024x1024 array, a full frame would consist of the entire 1024X1024 pixel area. In
the WinX/32 software, the number of frames to be acquired during a data acquisition
is determined 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.
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.
Gate Mode: PI-MAX3 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' during3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

PI-MAX®3 System Manual

196

Version 1.D

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 ispermanently 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-MAX3 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 73) 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.
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.

Appendix H

Glossary

197

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.
Filmless Gen III: Filmless Gen III devices use GaAsP photocathodes which have noion barrier film (MCP). The Gen III filmless intensifiers offer ultra-fast gating as wellas >50% QE for the best combination of sensitivity in the visible region (<780nm)
and gate speed.
Gen IV: Introduced in 1999. No ion barrier film and exhibit enhanced QE, SNR,
dynamic range, and high-light-level resolution.
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-MAX3 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.
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 Decay Time: A delay between the end of the exposure time and the beginningof the array readout. This time is inserted to allow the phosphor to decay to 1%
before readout occurs and will vary depending on the phosphor type.
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 (~ 2 µs decay). The P47 offers even faster decay (0.4 µs). The
phosphor decay time (see above), inserted between the end of the exposure time andthe beginning of the array readout, allows for the decay time.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

198

PI-MAX®3 System Manual

Version 1.D

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, phosphor
decay time elapses to allow for phosphor decay, and then the CCD array is readout.
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-MAX3 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.
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.
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.

Appendix H

Glossary

This page intentionally left blank.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

199

Declaration of Conformity
This section of the PI-MAX3 system manual contains the declaration of conformity for
PI-MAX3 systems. A system includes the PI-MAX3 with a Gen II or Filmless Gen III
intensifier and a PI-MAX3 power supply.

200

DECLARATION OF CONFORMITY
We, the undersigned
Manufacturer: Roper Scientific (Princeton Instruments)
Address, City: 3660 Quakerbridge Road, Trenton, NJ 08619
Country: USA
Authorized Representative in Europe: Roper Scientific, GmbH
Address, City: Rosenheimer Landstr. 87, D-85521, Ottobrunn
Country: Germany
Certify and declare under our sole responsibility that the following apparatus:
PI-MAX3 Camera with Power Supply,
Conforms to the emissions requirements of EN61326-1:2006; Clause 7.2:
CISPR 11 Edition 4: 2003
CISPR 11 Edition 4: 2003
IEC 61000-3.2: 2000
IEC 61000-3-3: 2002

Conducted Emissions, Class A
Radiated Emissions, Class A
Harmonics
Flicker

Conforms to the immunity requirements of EN61326-1:2006; Table 1:
IEC 61000-4-2: 2001
IEC 61000-4-3: 2002
IEC 61000-4-4: 2004
IEC 61000-4-5: 2001
IEC 61000-4-6: 2003
IEC 61000-4-11: 2004

Electrostatic Discharge
Radiated Immunity
EFT/Burst and Power Leads
Surge Immunity
Conducted Immunity and Power Leads
Voltage Dips and Interrupts

And follows the provisions of Low Voltage Directive and Safety:
CE Low Voltage Directive 2006/95/EC
Product Safety Regulations and Standards IEC 60950-1:2005
EMC Directive 2004/108/EC
The technical documentation is kept at the following address:
Company:
Address, City, State:
Country:
Telephone Number:
Fax Number:

Princeton Instruments
3600 Quakerbridge Rd, Trenton, NJ 08619
USA+1 800.874.9789/+1 609.587.9797+1 609.587.1970

Name and Position of Person Binding the Manufacturer or his Authorized Representative:
William Asher

Signature:

Vice President of New Product Development

Date: June 2, 2009

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

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
have complete 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.

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, all202

Warranty & Service

203

parts 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.

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

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

204

PI-MAX®3 System Manual

Version 1.D

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” withthe operation of the product or part, all invoices must be paid in full inaccordance with the terms of sale. Failure to pay invoices when due may result in
the interruption 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;
has been damaged as a result of misuse, improper installation, faulty or
inadequate maintenance or failure to follow instructions furnished by us;has had serial numbers removed, altered, defaced, or rendered illegible;
has been subjected to improper or unauthorized repair;
has been damaged due to fire, flood, radiation, or other “acts of God” orother contingencies beyond the control of Princeton Instruments; or
is a shutter which is a normal wear item and as such carries a onetime only
replacement due to a failure within the original 1 year Manufacturer
warranty.
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.

Warranty & Service

205
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: 1-800-874-9789 / 1-609-587-9797
Fax: 1-609-587-1970
Customer Support E-mail: techsupport@princetoninstruments.com
For immediate support in your area, please call the following locations directly:
North America

800 899 1144 (toll free) or 609 587 9797

France+33 (1) 60 86 03 65

Germany+49 (0) 89 660 7793

Japan

+81 (3) 5639 2741

UK & Ireland+44 (0) 1628 472 346

Singapore+65 6408 6240

China

+86 10 659 16460

Otherwise, see our Support web page at www.princetoninstruments.com.
An up-to-date list of addresses and telephone numbers is posted on the
www.princetoninstruments.com/Support page. In addition, links on this page
to support topics allow you to send e-mail based requests to the Customer
Support group.

3660 QUAKERBRIDGE ROAD
TRENTON, NJ 08619 USA

IndexA
A/D converters
dual ...................................................................... 63
standard ............................................................. 160
AC power requirements ........................................... 27
Accessories, alignment of ...................................... 187
Acton adapter instructions ..................................... 192
Acton Series spectrograph adapter instructions ..... 190
Adapter instructions
Acton ................................................................. 192
Acton Series spectrograph ................................. 190
IsoPlane SCT-320 spectrograph ........................ 193
Alarm
controller ......................................... xiii, 19, 72, 92
disabling of photocathode and MCP power xiii, 19,
72, 92protection circuit ................................................. 25
Alignment
Safe Mode operation ........................................... 66
Analog channels ...................................................... 63
Analog gain ............................................................. 62
ANSI C library ...................................................... 149
Application, typical ............................................... 132
AUX I/O interface
cable .......................................................... 148, 161
cable leads
GP INPUT 0 ................................................. 161
PRE-TRIG IN ............................................... 161
SyncMASTER1 ............................................ 161
SyncMASTER2 ............................................ 161
T0 Output ...................................................... 161
connector ........................................................... 147
connector pinout ................................................ 161
General Purpose Input 0 signal.......................... 162
Pre-Trigger Input signal .................................... 162
specifications ..................................................... 161
SyncMASTER1 Output signal .......................... 162
SyncMASTER2 (via 1 kOhm) Output signal .... 162
SyncMASTER2 (via 10 Ohm) Output signal .... 163
T0 Output signal ................................................ 162
AUX OUT output .................................................. 161

B
Backgroundbaseline level ..................................................... 144
DC level .............................................................. 45
Baseline level......................................................... 144
Baseline signal ......................................................... 45

excessive humidity ...................................... 45, 152
sudden change in ......................................... 45, 152
Binningcomputer memory burden ................................... 56
hardware .............................................................. 56
interline CCD .................................................. 57
restrictions due to well capacity ...................... 56
readout time ......................................................... 56
resolution loss ...................................................... 56
softwareeffect on S/N ratio ........................................... 62high light level measurements ........................ 62
shot-noise limited measurements .................... 62
Blooming ................................................................. 49
Bracket pulsing
effect on coincidence timing ......................... 74, 94
impact on coincidence timing ......................... 75, 95
need for .......................................................... 73, 93

C
Cables
AUX I/O ............................................................ 148
Ethernet .............................................................. 148
Calibration
spectroscopy
suitable light sources............................. 186, 188
Cameramounting considerations
orientation constraints ............................. 28, 181
use of mounting bracket for security ...... 28, 181
Camera Detection wizard ........................................ 31
Cautions
DMA and Interrupt ............................................ 155
excessive humidity in CCD chamber .......... 45, 152
need to contact factory in case of sporadic orcontinuous unwarranted alarms..................... 144
sporadic or continuous unwarranted alarms xiii, 19,
49, 72, 92
CCD arraybinning................................................................. 56
blooming ............................................................. 49
maximum on-chip integration ............................. 49
readout of ............................................................. 50
readout theory...................................................... 54
shift register ......................................................... 54
shutter function ..................................................... 49
signal-to-noise ratio vs on chip integration time . 49
theory of operation .............................................. 49
well capacity ........................................................ 49

206

IndexCirculator hoses ....................................................... 30
Circulator, closed ................................................... 147
Cleaning.................................................................... 20
Cleaning optical surfaces
protective window ................................................ 20
Unigen II coating .......................................... xiii, 20
C-mount lens, installation and removal ................. 180
Coincidence, how to measure ................................ 140
Connectors
AUX I/O ............................................................ 148
AUX OUT ......................................................... 161
LOGIC OUT ............................................. 147, 161
Monitor .............................................................. 161
PI-MAX3, Power/Signal ................................... 146
READY ............................................................. 160
TRIGGER IN .................................................... 160
Contact information ............................................... 205
Controller gain ......................................................... 62
CoolCUBEII circulator
outline drawing .................................................. 172
specifications ..................................................... 165
Coolingand vacuum ....................................................... 155
coolant mixture .................................................. 148
dry nitrogen ......................................................... 31
photocathode ....................................................... 31
troubleshooting .................................................. 154
C-type lens mount .................................................. 180
Customer support ................................................... 205

DDanger Notices
high voltage ......................................................... 25
Dark charge
dynamic range ..................................................... 49
Dark charge pattern ............................................... 144
Dark current ........................................................... 194
Data cable ............................................................... 148
Depth of field ......................................................... 143
Detectors, rotation of ..................................... 187, 188
DIF
requirements ...................................................... 115
DIF gating mode
requirements ...................................................... 123
DIF operation......................................................... 115
Digitization .............................................................. 63
Dual A/D converters ................................................ 63
Dual Image Feature ........................................ See DIF
Dynamic range ......................................................... 49

E
EBI............................................. 31, 65, 141, 160, 194
Equivalent Background Illumination (EBI) ...... 31, 65,
141, 160, 194
Ethernet card
I/O address, DMA channel, and interrupt level . 155

207
Ethernet network is not accessible ......................... 155
Excess Rep Rate indicator ..................................... 147
Excessive humidity .................................. 45, 152, 153
Experiment types ............................................... 77, 97
Exposure and Readout............................................... 43

F
Fan ................................................................... 26, 147
Fast mode
data acquisition .................................................... 66
flowchart ............................................................. 67
image update lag.................................................. 66
First light ............................................................ 34, 38
Fluorescence experiment, typical .......................... 132
Focusing
C-mount or F-mount lenses ............................... 181
spectrograph ...................................................... 186
Full frame CCD
readout rate .......................................................... 55
Full frame readout ................................................... 54

G
Gate Width and Delay optimization ...................... 141
Gated operation
advantages of ................................................. 71, 91
extended-exposure pulsing ............................ 73, 93
General Purpose Input 0 signal .............................. 162
General Purpose Input cable lead .......................... 161
GigE output ........................................................... 160
GP INPUT 0 cable lead ......................................... 161
Grounding and safety (PI-MAX3) ........................... 18
Grounding and safety (power supply) ..................... 18

H
Hardware binning .................................................... 56
Heat removal block ................................................ 148
High level radiation, definition of ......................... 139
Hose connections ..................................................... 30

I
I.I.T. switch............................................................ 147
IEC Publication 348................................................. 18
image intensifier gain ............................................... 65
Inhibiting gating during readout ............................ 143
Installation ............................................................... 25
PCI drivers .......................................................... 29
software ............................................................... 29
Intensifier
MCP .................................................................... 49
Intensifier alarmdisabling of photocathode and MCP power ...... 144
reason for ........................................................... 144
required response............................................... 144
Interface card
driver installation................................................. 29
Interline CCD

208

PI-MAX®3 System Manual

hardware binning ................................................. 61
non-overlapped operation .................................... 51
readout rate .......................................................... 53
Internal pulser ........................................................ 164
Invert LOGIC check box ................................. 64, 147
IsoPlane SCT-320 spectrograph adapter instructions........................................................................... 193

L
Lasersfree-running ....................................................... 142
jitter ................................................................... 143
overview ............................................................ 142
triggered ............................................................ 142
Lens
depth of field ..................................................... 143
focusing ............................................................. 181
installation and removal .................................... 180
lens coupling effects ............................................ 17
mounting ...................................................... 28, 180
performance considerations ............................... 143
throughput ......................................................... 143
LightField .............................................................. 149
LOGIC OUT levels
Acquiring............................................................. 63
Image Shift .......................................................... 63
Invert LOGIC check box ............................. 64, 147
Logic 1 ................................................................ 63
Read Out.............................................................. 63
Shutter ................................................................. 63
Wait for Trigger .................................................. 63
LOGIC OUT output............................................... 161

M
Maintenance .............................................................. 20
MCP................................................................... 15, 49
MCP bracket pulsing .............................. 73, 74, 93, 94
MCP gating option................................................. 131
Microchannel Plate (MCP) ...................................... 49
Monitor output ....................................................... 161
Mounting a spectrograph ......................................... 28

N
Nitrogen ................................................................... 31
Non-Overlapped operation, example ....................... 51

O
Orientation correction .............................................. 40
Outline drawings
CoolCUBEII Circulator...................................... 172
PI-MAX3 Power Supply ................................... 171
PI-MAX3 with C-mount adapter ....................... 168
PI-MAX3 with F-mount adapter ....................... 169
PI-MAX3 with Spectroscopy-mount adapter .... 170
Overexposure protection........................................ 139

Version 1.D

P
Peltier type cooler .................................................... 15
Phosphor decay time .............................................. 122
PICam .................................................................... 149
Picosecond gating .................................................. 135
PI-MAX3
1024x256
orientation correction ...................................... 40
grounding and safety ........................................... 18
rear panel features ............................................. 146
Power cord................................................................ 27
Power requirements ................................................. 27
Power supply
grounding and safety ........................................... 18
outline drawing .................................................. 171
Power/Signal connector, PI-MAX3 ....................... 146
PRE-TRIG IN cable lead ....................................... 161
Pre-Trigger Input cable lead .................................. 161
Pre-Trigger Input signal ......................................... 162
Pulserinhibiting during readout ................................... 143
internal............................................................... 164

Q
QE curves .............................................................. 164
Quantum Efficiency curves ................................... 164

R
Readout
binning................................................................. 56
inhibiting gating during readout ........................ 143
subsection of array .................................. 52, 53, 55
Readout pattern, subtractable................................. 144
Readout rate
control of ............................................................. 63
precision vs speed tradeoff .................................. 63
Readout times
full frame CCD .................................................... 55
interline CCD ...................................................... 53
READY output ...................................................... 160
Requirements
power ................................................................... 27
ventilation ............................................................ 26
Resolution, loss of with binning .............................. 56

S
S/N ratio............................................................. 49, 62
Safe mode
as used for setting up ........................................... 66
fast image update ................................................. 66
flowchart ............................................................. 67
missed events....................................................... 66
Saturation ................................................................. 49
Setup ........................................................................ 25
Shift register ............................................................ 54
Signal and Gate coincidence requirements ............ 139

IndexSignal delay ........................................................... 139
adjustment of to achieve coincidence ................ 141
Signal-to-noise ratio
on-chip integration .............................................. 49
Software binning...................................................... 62
Specifications
AUX I/O connector ........................................... 161
computer ............................................................ 165
CoolCUBEII circulator ...................................... 165
general ............................................................... 158
internal pulser .................................................... 164
operating environment ....................................... 166
Spectrographs
Acton Series ...................................................... 186
adapters ............................................................... 28
focusing and alignment ..................................... 186
IsoPlane SCT-320 ............................................. 186
Sub-nanosecond gating ............ See Picosecond gating
SyncMASTER1 cable lead .................................... 161
SyncMASTER1 Output signal .............................. 162
SyncMASTER2 (via 1 kOhm) Output signal ........ 162
SyncMASTER2 (via 10 Ohm) Output signal ........ 163
SyncMASTER2 cable lead .................................... 161

T
T0 OUT cable lead ................................................ 161
T0 Output signal .................................................... 162
Technical support .................................................. 205
Temperature
control problems ................................................ 154
Temperature control .................................................. 48
effect of vacuum deterioration........................... 155
loss of lock ........................................................ 144
thermal protection switch .................................. 144
time to lock................................................... 47, 148
time to stabilize ................................................. 144
Temperature lock ..................................................... 48
Theory of operation .................................................. 16
Thermal protection switch ..................................... 144
Time budget ........................................................... 139
Timing coincidence, how to achieve ..................... 139
Tips and Tricks ...................................................... 139
Trigger In LED .............................................. 147, 160
Troubleshooting
cooling ............................................................... 154
Ethernet network is not accessible .................... 155

209
temperature lock ................................................ 155
vacuum deterioration ......................................... 155

U
Unigen II coating ................................................... xiii
Unpacking and initial inspection ............................. 25

V
Vacuum deterioration ............................................ 155
Ventilation fan ....................................................... 147
Ventilation requirements ......................................... 26
Vignetting ................................................................ 17W
Warnings
Controller/Detector cable .................................. 148
damage from operating camera that has lost its
nitrogen backfill .............................................. 20
destruction of intensifier caused by excess light139
F-mount cameras and nose-up operation ..... 28, 180
need for cooling water to be at ambient temperature........................................................................ 48
operation without evacuation or backfill ............. 20
protective grounding ........................................... 18
replacement powercord ....................................... 18
touching the CCD array ....................................... 19
Warranties
image intensifier detector .................................. 203
one year ............................................................. 202
one year on refurbished/discontinued products . 202
owner's manual and troubleshooting................... 203
sealed chamber .................................................. 202
software ............................................................. 203
vacuum integrity ................................................ 203
XP vacuum chamber ......................................... 202
x-ray detector..................................................... 203
your responsibility ............................................. 204
Water ports ............................................................ 147
Website .................................................................. 205
Well capacity
blooming ............................................................. 49
dark charge .......................................................... 49
restrictions on hardware binning ......................... 56
saturation ............................................................. 49
WizardCamera Detection ................................................ 31