Basler acA2000-165, User Manual

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Image Acquisition Control AW00123402000
114 Basler ace USB 3.0
6.6.2 Rolling Shutter
(acA1920-25, acA2500-14, acA3800-14,
acA4600-10 Only)
The acA1920-25um/uc, acA2500-14um/uc, acA3800-14um/uc, and acA4600-10uc cameras are
equipped with an electronic rolling shutter. The rolling shutter is used to control the start and stop
of sensor exposure. The rolling shutter used in these cameras has two operating modes: electronic
rolling shutter mode and global reset release mode.
Electronic Rolling Shutter Mode
When the shutter is in the electronic rolling shutter (ERS) operating mode, it exposes and reads out
the pixel lines with a temporal offset (designated as tRow) from one line to the next. When frame
start is triggered, the camera resets the top line of pixels of the ROI (line one) and begins exposing
that line. The camera resets line two tRow later and begins exposing the line. The camera resets
line three tRow later and begins exposing the line. And so on until the bottom line of pixels is
reached (see Figure 50).
The exposure time is the same for all lines and is determined by the Exposure Time parameter
setting.
The pixel values for each line are read out at the end of exposure for the line. Because the readout
time for each line is also tRow, the temporal shift for the end of readout is identical to the temporal
shift for the start of exposure.
The Sensor Readout Time is the sum of the readout times of all lines. The Total Readout Time
equals the Sensor Readout Time plus the Exposure Overhead time C
1
.
Camera Model Temporal Shift tRow [µs]
acA1920-25um/uc 35 µs
acA2500-14um/uc 35 µs
acA3800-14um/uc TBD µs
acA4600-10uc TBD µs
Table 23: Temporal Shift for Start of Exposure Between Two Consecutive Lines
Camera Model Exposure Overhead C
1
[µs]
acA1920-25um/uc 490 µs
acA2500-14um/uc 490 µs
acA3800-14um/uc TBD µs
acA4600-10uc TBD µs
Table 24: Temporal Shift for Start of Exposure Between Two Consecutive Lines