xiJ - Technical Manual Version 0.06
44
4.1.5.
Acquisition modes
4.1.5.1.
Free-Run
Also known as continuous acquisition. In this mode the sensor delivers a constant stream of image data at the maximum speed
available by the current bandwidth, without any external trigger. Each image exposure is sequentially started automatically when
possible.
For all sensors the exposure of the next frame overlaps with the data readout of the previous frame.
This Overlapped mode gives the highest number of frames per second (FPS).
figure 4-8, acquisition mode - free run
In this mode the timing depends on the Exposure Time and Data Readout Time.
4.1.5.2.
Trigger controlled Acquisition/Exposure
Unlike in the free-run, each image exposure can also be triggered with an input trigger signal. In this mode, the sensor waits
in stage until the trigger signal arrives. Only then, the exposure of first frame is started, which is followed by the data readout.
Software Trigger
The trigger signal can be sent to the sensor using a software command. In this case, common system related latencies and
jitter apply.
Hardware Trigger
A hardware trigger can be sent to the sensor using the digital input described in
3.8.3 Optically isolated Digital Input
. Triggering
by hardware is usually used to reduce latencies and jitter in applications that require the most accurate timing.
