Point Grey Flea3 GigE Technical Reference
7 Image Acquisition
7.1.6
Multiple Exposure Pulse Width Trigger (Mode 5)
Trigger Mode 5 allows the user to set the number of triggered images to be exposed before the image readout starts. In
the case of Trigger Mode 5, the shutter time is controlled by the trigger pulse duration; the minimum resolution of the
duration is generally 1 tick of the pixel clock (see
PIXEL_ CLOCK_ FREQ: 1AF0h
). The resolution also depends on the
quality of the input trigger signal and the current trigger delay.
In the figure below, the camera starts integration of incoming light from the first external trigger input falling edge and
exposes incoming light until the trigger is inactive. Repeat this sequence for N (parameter) external trigger inputs then
finish integration. Parameter is required and shall be one or more (N ≥ 1).
Figure 7.5: Trigger Mode 5 (“Multiple Exposure Pulse Width Mode”)
Registers—
TRIGGER_MODE: 830h
Presence
[0]
1
ON
[6]
1
Polarity
[7]
Low/High
Source
[8-10]
GPIO Pin
Value
[11]
Low/High
Mode
[12-15]
Trigger_Mode_5
Parameter
[20-31]
N ≥ 1 number of images exposed
before image readout starts
Revised 10/29/2013
Copyright ©2010-2013 Point Grey Research Inc.
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