Basler acA2000-165, Руководство пользователя

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AW00123402000 Image Acquisition Control
Basler ace USB 3.0 119
For more information about the Exposure Time parameter, see Section 6.5 on page 110 .
Flash Window in Global Reset Release Operating mode
If you are using the global reset release mode, you should use flash exposure for capturing images
of both stationary and moving objects. If you don’t use flash exposure when capturing images of
stationary objects, the brightness in each acquired image will vary significantly from top to bottom
due to the differences in the exposure times of the lines. If you don’t use flash exposure when
capturing images of moving objects, the brightness in each acquired image will vary significantly
from top to bottom due to the differences in the exposure times of the lines and the images will be
distorted due to the temporal shift between the end of exposure for each line.
You can avoid these problems by using flash lighting and by applying the flash during the "flash
window" for each frame. The flash window is the period of time during a frame acquisition when all
of the lines in the sensor are open for exposure.
Figure 53 illustrates the flash window for the global reset release mode.
In global reset release mode, the flash window opens when the frame is triggered and closes after
a time period equal to the Exposure Time parameter setting. Thus, the flash window width (i.e., how
long the flash window will remain open) is equal to the Exposure Time parameter setting.
Line 1
Line 2
Line 4
Line 3
Line 5
Line 6
Line 8
Line 7
Line 9
Line 10
Line 11
Line N-2
Line N
Line N-1
Time to Flash Window Open
tRow
Flash Window Width
= line exposure time
= line readout time
Flash Window
Fig. 52: Flash Window for Rolling Shutter in the ERS Mode