Triggering and timings
81
Alvium USB Cameras User Guide V1.1.0
Triggering with rolling shutter cameras
This section describes triggering behavior for 1800 U-500 cameras with rolling
shutter sensor.
shows how an external signal triggers exposure and readout for cameras
with rolling shutter sensors. As for global shutter sensors, readout has a constant
duration, acquisition must be active to enable exposure, the end of exposure starts
readout.
ERS sensors run in cycles where
readout area
equals
exposure area
. Overlapping
triggering is not supported. If exposure time is shorter than readout time,
exposure starts with a delay:
Exposure start delay
=
exposure area
– exposure time
1. Exposure time is shorter than readout time.
Trigger 1 starts exposure 1 with a delay
2. Exposure time is shorter than readout time, but
longer
than for exposure 1.
Trigger 2 starts exposure 2 with a delay
shorter
than for exposure 1.
3. Exposure time is longer than readout time.
Trigger 3 starts exposure time without a delay. Because the
exposure area
is
longer, also the
readout area
is longer than for triggers 1 and 2.
4.
Exposure area
is ongoing.
Trigger 4 is ignored.
5.
Readout area
is ongoing.
Trigger 5 is ignored.
6.
Readout area
is finished. Exposure time is longer than readout time.
Trigger 6 starts exposure 6 without a delay.
Figure 45: Triggering rolling shutter cameras
Available values for TriggerSelector
Cameras with rolling shutter
can
be triggered using
AcquistionStart
,
AcquisitionEnd
, or
FrameStart
for
TriggerSelector
.
Cameras with rolling shutter
cannot
be triggered using
ExposureStart
or
ExposureEnd
for
TriggerSelector
.
External signal
Sensor state
1
2
3
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ZĞĂĚŽƵƚĐƟǀĞ
4
5
6
1
1
2
2
3
3
Readout area
Exposure area
Delay
П
Delay
П
Idle
Readout area
Exposure area
Readout area
Exposure area
П
Exposure start delay
Legend
