8.Features
© China Daheng Group, Inc. Beijing Image Vision Technology Branch 60
Sensor
Exposure
Time
Frame N
Frame N+1
Frame N+2
Frame N
Frame N+1
Sensor
Readout
Trigger
Trigger
Trigger
Figure 8-23 The trigger acquisition exposure sequence diagram in non-overlaping exposure mode
Overlaping exposure
In overlaping exposure mode, the current frame image exposure process is overlaping with the readout of
the previous frame. That is, when the previous frame is reading out, the next frame image has been started
exposure. As shown in the Figure 8-24, when the N
th
frame image is reading out, the N+1
th
frame image
has been started exposure.
The formula of overlaping exposure frame period:
overlaping
exposure frame period ≤ exposure time + readout time
Time
Overlaping area
Overlaping area
Frame N
Frame N+1
Frame N+2
Frame N
Frame N+1
Sensor
Exposure
Sensor
Readout
Blank
Blank
Figure 8-24 The exposure sequence diagram in overlaping exposure mode
Trigger_mode OFF
If the exposure time is greater than the frame blanking time, the exposure time and the readout time will
be overlapped. As shown in the Figure 8-24.
Trigger_mode ON
When the interval between two triggers is less than the sum of exposure time and the readout time, it will
occur overlaping exposure, as shown in Figure 8-25.