Page 14 ·
EQ-99 Manager
User’s Manual
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Shutter Closed
Shutter Open
0V
5V
Shutter
State
Trigger
Input
Positive Level
Likewise, with a negative level, the logic is reversed, and the shutter is open
when voltage is low and closed when voltage is high:
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Shutter Closed
Shutter Open
0V
5V
Shutter
State
Trigger
Input
Negative Level
When using the timed exposure mode, you specify how long the shutter is to
remain open for each trigger. Exposure timing is only valid for edge (positive or
negative) trigger modes. Below is a timing diagram of positive edge trigger
mode and an exposure time of 200ms:
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Shutter Closed
Shutter Open
0V
5V
Shutter
State
Trigger
Input
Positive Edge, Exposure = 200ms
Care should be taken to ensure your trigger input does not exceed the 2Hz
(500ms) operating speed of the shutter. Operating above that rate will lead to
unexpected exposure times. Below is an example of shutter operation with a
positive edge input in manual mode. As you can see, the shutter does not open
on every other pulse, as you would expect, but rather, the instrument delays the
opening until the 500ms after the last open trigger, leading to the varied
exposure times:
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Shutter Closed
Shutter Open
0V
5V
Shutter
State
Trigger
Input
Positive Edge, Manual, Trigger Speed Exceeds Shutter Capability
