IDS Software Suite 4.96.1

In trigger mode, the sensor is on standby and starts exposing on receipt of a trigger signal. A trigger event can be initiated by a software command (software trigger) or by an electrical signal via the camera’s digital input (hardware trigger). For the specifications of the electrical trigger signals, see the D: Specifications chapter.

The trigger mode is selected using is_SetExternalTrigger().

•Software trigger mode
When this mode is enabled, calling is_FreezeVideo() immediately triggers the capture of an image and then transfers the image to the PC. If is_CaptureVideo() is called, the triggering of image capture and the transfer of images are performed continuously.

•Hardware trigger mode
When this mode is enabled, calling is_FreezeVideo() makes the camera ready for triggering just once. When the camera receives an electrical trigger signal, one image is captured.
If you call is_CaptureVideo(), the camera is made ready for triggering continuously. An image is captured and transferred each time an electrical trigger signal is received; the camera is then ready for triggering again (recommended procedure).

•Hardware trigger mode with burst trigger (USB 3 and GigE uEye cameras)
The burst trigger mode is enabled by the is_Trigger() function. In burst trigger mode, the camera captures a series of images in rapid succession on receipt of a single trigger signal. The trigger signal can be transmitted via external hardware trigger via the digital input of the camera. is_CaptureVideo() is used for image acquisition because multiple images have to be transferred.

•Hardware trigger mode with trigger prescaler (some uEye camera models only)
In addition, you can set a trigger prescaler with the is_Trigger() function. With the trigger prescaler, you define that an image capture is triggered for example with every 20th trigger signal and not with every trigger signal. This function can be used if the trigger signal delivers more pulses as needed for the captures. For image acquisition, is_CaptureVideo() is recommended as the camera is made ready for triggering continuously.

•Freerun synchronization
In this mode, cameras running in freerun mode (live mode, see Image capture in freerun mode) can be synchronized with an external trigger signal. The cameras still remain in freerun mode. The trigger signal stops and restarts the current image capture process. You can use this mode to synchronize multiple cameras that you are operating in the fast live mode. Not all camera models support this mode (see is_SetExternalTrigger()).

In trigger mode, the maximum frame rate is usually lower than in freerun mode because the sensors expose and transfer sequentially. The possible frame rate in trigger mode depends on the exposure time.

Some sensors support an overlap trigger mode (see Camera and sensor data). This feature allows overlapping the trigger for a new image capture with the readout of the previous image. These sensors provide almost the same frame rate in trigger mode as in freerun mode. With these sensors, the possible frame rate in trigger mode is independent of the exposure time.

For more information on the capture modes of the uEye cameras see also Camera basics: Trigger.