8.Features
© China Daheng Group, Inc. Beijing Image Vision Technology Branch 34
Avoid overtriggering in Timed exposure mode. If the Timed exposure mode is enabled, do not attempt to
send a new trigger signal while the previous exposure is still in progress. Otherwise, the trigger signal will
be ignored, and a FrameStartOvertrigger event will be generated.
b)
TriggerWidth exposure mode
In TriggerWidth exposure mode, the length of exposure is determined by the width of the external trigger
signal. This function can meet the needs of users to change the exposure time of each frame of image.
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If rising edge triggering is enabled, exposure starts when the trigger signal rises and continue until the
trigger signal falls, as shown in Figure 8-14
Exposure
External trigger signal
Figure 8-14 The sequence diagram in rising edge trigger of TriggerWidth exposure mode
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If falling edge triggering is enabled, exposure starts when the trigger signal falls and continue until the
trigger signal rises, as shown in Figure 8-15
Exposure
External trigger signal
Figure 8-15 The sequence diagram in falling edge trigger of TriggerWidth exposure mode
Avoid overtriggering in TriggerWidth exposure mode. If the TriggerWidth exposure mode is enabled, do
not send trigger signals at too high a rate. Otherwise, trigger signals will be ignored, and a
FrameStartOvertrigger event will be generated.
The trigger signal width of the external triggering should not be shorter than the value of the entered
ExposureOverlapTimeMax parameter.
8.2.7.2.
Set Exposure Value
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Global Shutter
The VENUS camera (VEN-161-61U3M-(M01/M05/M06)) uses global shutter sensors. The implementation
process of global shutter is as shown in Figure 8-16, all the lines of the sensor are exposed at the same
time, and then the sensor will read out the image date one by one.
The advantage of the global shutter is that all the lines are exposed at the same time, and the images do
not appear offset and distortion when capturing moving objects.
