Laser Shutter Systems
SR470 Series — Laser shutters and controllers

SR470 Series Shutter Systems· Ultra-low vibration shutter head
· True mechanical laser beam blocking· >10 M cycle lifetime· Microprocessor controlled timing· DC to 100 Hz· Easy to align 3 mm aperture· GPIB, RS-232 and Ethernet

Introducing two new optical shutter systems from SRS — theSR470 Laser Shutter Controller and SR474 Four-Channel
Laser Shutter Driver. These shutter systems are designed
specifically to minimize vibration on your optical table.
They are built around a unique shutter head design, supportedby one of two available controller models. The SR470
provides timing signals to a single shutter head, while themulti-channel SR474 drives up to four shutter heads, and iscontrolled by external timing signals.
The Shutter Head
Unlike conventional solenoid based shutters, the SR475
shutter head contains a closed-loop DSP control system thatprecisely guides the shutter blade between open and closed
positions, never encountering physical stops. Vibration andmechanical noise are kept to a minimum, leaving your optical
table disturbance-free.
The shutter blade is mounted between sapphire jewel bearings
that minimize friction and result in a head lifetime in excess

The SR475’s unique beryllium-copper shutter
blade driven with rare earth magnets

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SR470 Series Laser Shutter Systemsof 10 M cycles — orders of magnitude more than is typicallyfound in shutter heads.
The 3 mm clear aperture is designed for easy alignment and islarge enough to be used with common light sources. Typicalrise and fall times are under 500 µs, and repetition rates fromDC to 100 Hz can be used. Unlike other shutters, the SRS
shutter is not duty cycle limited — you can run any duty cycle
you choose.

In addition to triggered sequences, the SR470 can also act
as a driver to actuate the shutter head from your own timingsignals. You can also manually control the shutter from thefront panel.
Remote operation is supported with GPIB, RS-232 andEthernet computer interfaces. All instrument functions canbe controlled and read over any of the interfaces. Up tonine complete instrument configurations can be saved in
non-volatile RAM and recalled at any time. Shutter faults
are automatically detected and reported with audible andelectronic (TTL) alarms.
SR474 Four-Channel Driver
The SR474 Four-Channel Driver interfaces with up to four
shutter heads. Rear-panel TTL level inputs are provided foryour external timing signals. Each of the four channels can be
set for normally open or normally closed operation.
Each channel has a front-panel State button which allows
you to manually change the shutter state. The channel Source
buttons set each channel to manual, external TTL or remotestate control. Each channel also has an Align button that drives
its shutter head at a 1 Hz rate making laser alignment simple.
The Global Control section of the front-panel allow you to set
or reset all channels to their “normal” states.

SR475 Shutter Head with cover removed,
revealing control system electronics
SR470 Controller
The SR470 Shutter Controller allows you to generate timing
signals for the shutter head. You have complete control of theexposure time, which can be set between 4 ms and 10,000 s
with 0.1 ms resolution. Pre- and post-exposure delays can also
be configured. A bright green 8-digit LED display shows thecurrent parameter in seconds or hertz, and timing is accurate
to 100 ppm.

As with the SR470, remote operation is supported with GPIB,
RS-232 and Ethernet computer interfaces. All instrument
functions can be controlled and read over any of the interfaces.
Shutter faults are automatically detected and result in audible,visible and electronic alarms.
Performance and Reliability
The SR470 and SR470 Laser Shutter systems from SRS offer
performance and reliability not found in other systems. For
more details call us at 408-744-9040.

A variety of trigger modes are provided — internal, external,
front panel, and continuous — giving you the flexibility tohandle just about any application. Triggered bursts frommilliseconds to months can also be generated, placing theSR470 in a class of its own.

SR470 rear panel

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SR474 rear panelSR470 Series Specifications

SR475 Laser Shutter Head

Display blanking

Mechanical

GeneralShutter blade
Clear aperture
Repetition rate
Exposure rise/fall time
Min. exposure time
Insertion delay jitter

Interfaces

BeCu alloy, black oxide finish
0.120 in. min. diameter
100 Hz500 µs typ., in full-speed
5 ms
10 µs rms typ.
(measured at 10 Hz rep rate)
Bearing
Sapphire jewel bearing
Blade position
Closed-loop (PID) controlled.
Can be operated as NO or NC.
Opening/closing bounce None allowed
Operating temperature 0 °C to 35 °C
Mounting
Any orientation
GeneralMax. cable length
WeightDimensions
Power3m
1 lbs.
2.25" × 1.6" × 1.0" (WHD)
4.5 VDC @ 250 mA
12 VDC @ 1.25 A

Shutter alignment
Save/recall
Auxiliary I/O ports
Control input

Sync out
PowerDimensions
WeightWarranty

Front panel LEDs can be disabled.

GPIB, RS-232 and Ethernet.
All instrument functions arecontrollable over the interfaces.
Align button chops shutter at 1 Hz
Nine sets of instrument settings canbe saved and recalled.
Rear-panel Aux I/O 1 & Aux I/O 2.
TTL level, multi-purpose ports.
Context sensitive TTL input.
Triggers on falling edge. TTL-Hi
resets to Normal state. TTL-Lo
sets to Normal state.
Rear-panel TTL level output.
40 W, 90 to 264 VAC, 47 to 63 Hz
7.95" × 3.37" × 10.25" (WHL)
7 lbs.
One year parts and labor on defects
in materials and workmanship.

SR474 Four-Channel DriverOperation

SR470 Controller
TimingResolutionAccuracy
Pre-exposure delay
Exposure time
Post-exposure delay
Repetition rate
Initial state
Shutter type.
Triggering

100 µs (8-digit display)
100 ppm
0 to 10,000 s
4 ms to 10,000 s (shutter limited)
4 ms to 10,000 s (shutter limited)
Shutter limited
Normally open or closed(user defined)
SR470 Series Laser Shutters

Triggered burst

Internal, external TTL, external
level, and front-panel, continuous
1 to 99,999,999 timing cycles

System Fault and Alarms
Fault LED indicator, audible alarmand rear-panel TTL output. System
automatically detects shutter fault.

Display
TypeChannel enable
Global control
Shutter alignment

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Front-panel Source button selects
external TTL, manual or remote(computer interface) state control.

System Fault and Alarms
Alarm types

Fault LED indicators, audible
alarm and rear-panel TTL output.
System automatically detects
shutter fault.

General
Display blanking

7-segment LED, 8-digit

SR470 Series Laser Shutters
Shutter state can be controlled
manually from front-panel orfrom external TTL timing signals.
Front-panel Enable buttons enable
or disable each channel.
Sets or resets all channels to their“Normal” states.
Front-panel Align buttons cause
selected channels to change state at
a 1 Hz rate for easy laser alignment.

Triggering
Modes

Modes

Alarm types

Shutter type
Shutter state

Front panel LEDs can be disabled.

SR470 Series Specifications

Interfaces

Auxiliary I/O port
Shutter polarity

PowerDimensions
WeightWarranty

GPIB, RS-232 and Ethernet.
All instrument functions arecontrollable over the interfaces.
Rear-panel Aux I/O, TTL level“Normally Open” and “NormallyClosed” states for each channel are
set on rear-panel DIP switch.
75 W, 90 to 264 VAC, 47 to 63 Hz
7.95" × 3.37" × 10.25" (WHL)
7 lbs.
One year parts and labor on defects
in materials and workmanship(SR475 and SR476 shutter heads arewarranted for 90 days)

About the Shutter Heads
Unlike conventional designs, the SR475 Shutter Head can bemounted on your optical table in any orientation. This gives
you complete flexibility to route the mating cable out of theway of your experiment.
The aperture is positioned very close to the chassis edge,
making the SR475 ideal for chopping one of two parallel
beams separated by less than a centimeter. It also allows you
to operate your lasers very close to the plane of your optical
table top.
The small size of the shutter heads make them ideal in tightquarters, and with a precision guided blade, shutter vibration
is essentially eliminated.

0.12 clear aperture (SR475)
0.04 clear aperture (SR476)

1.600

1.000

0.875

0.687

8-32

8-32
0.000

SR470
SR474
O470RMSO470RMD
SR475

Shutter controller
4-ch. shutter driverSingle rack mount kit for SR47X
Double rack mount kit for SR47X
Shutter head (100 Hz)

Front View

2.250

1.125

Left View

0.750

connector

0.000
0.187

Ordering Information

1/4-208-32

1.000

Bottom View

(All dimensions in inches)

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Right View