Electronic Shutter Operation; Global Shutter (All Cameras Except Aca1920-25, Aca2500-14, Aca3800-14, Aca4600-10) - Basler acA2040-55 User Manual

Image Acquisition Control
6.6

Electronic Shutter Operation

All ace cameras are equipped with imaging sensors that have an electronic shutter. There are two
types of sensors that differ by design and support either the global or the rolling shutter mode .
Some of the sensors with a rolling shutter also support the global reset release shutter mode which
is a variant of the rolling shutter mode.
All ace models except the acA1920-25um/uc, acA2500-14um/uc, acA3800-14um/uc, and
acA4600-10uc use sensors with only global shutter modes. Some of the sensors with global shutter
allow to choose between "normal" or "fast" sensor readout.
The sensors of the acA1920-25um/uc, acA2500-14um/uc, acA3800-14um/uc, and acA4600-10uc
camera models support the rolling shutter mode and the global reset release shutter mode.
The following sections describe the differences between the shutter modes.
6.6.1 Global Shutter
acA2500-14, acA3800-14, acA4600-10)
All camera models other than the acA1920-25um/uc, acA2500-14um/uc, acA3800-14um/uc, and
acA4600-10uc are equipped with an electronic global shutter. On cameras equipped with a global
shutter, when frame acquisition is triggered, exposure begins for all lines in the sensor as shown in
Figure 61. Exposure continues for all lines in the sensor until the programmed exposure time ends
(or when the frame start trigger signal ends the exposure time, if the camera is using the trigger
width exposure mode). At the end of the exposure time, exposure ends for all lines in the sensor.
Immediately after the end of exposure, pixel data readout begins and proceeds in a linewise fashion
until all pixel data is read out of the sensor.
A main characteristic of a global shutter is that for each frame acquisition, all of the pixels in the
sensor start exposing at the same time and all stop exposing at the same time. This means that
image brightness tends to be more uniform over the entire area of each acquired image, and it helps
to minimize problems with acquiring images of objects in motion.
The cameras can provide an exposure active output signal that will go high when the exposure time
for the first line begins and will go low when the exposure time for the last line ends.
The sensor readout time (see
depends on ROI height. You can determine the readout time for a frame by checking the value of
the camera's SensorReadoutTime parameter.
142
(All Cameras Except acA1920-25,
Figure 61) is the sum of the line readout times and therefore also
AW00123409000
Basler ace USB 3.0