Dalsa Linea HS Series, Руководство пользователя

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Camera Performance and Features
Camera Performance and
Features
This section is intended to be a progressive introduction to the features of the camera, including
explanations of how to use them effectively.
Synchronizing to Object Motion
Acquiring Images: Triggering the Camera
Related Features: Trigger Mode, Trigger Source, Trigger Activation
A number of different methods that can be used to trigger image acquisition in the camera:
Internal Trigger
The simplest method is to set the Trigger Mode feature to “Internal”. This results in the camera
being triggered by an internal timer, which can be adjusted using the Acquisition Line Rate feature.
External Triggers
When the Trigger Mode feature is set to “External”, the triggers to the camera can come from
different sources, set using the Trigger Source feature.
The available sources for the triggers are from pin 5 of the GPIO connector, from the Camera Link
HS frame grabber, or from the rotary encoder feature (using pin 5 and pin 6 of the GPIO
connector).
Use the Trigger Activation feature to select the edge that triggers the camera. The options are:
Rising Edge, Falling Edge or Any Edge. When using Any Edge be careful that the time between
edges does not exceed the maximum line rate of the camera. If the line rate is exceeded one of
those edges will be ignored.
CamExpert can be used to configure the frame grabber for routing the encoder signal from the
frame grabber input to the trigger input of the camera via the Camera Link HS data cable.
Line Rate & Synchronization
A continuous stream of encoder trigger pulses synchronized to the object motion establishes the
line rate. The faster the object’s motion is, the higher the line rate. The camera can accommodate
up to its specified maximum frequency. If the maximum frequency is exceeded, the camera will
continue to output image data at the maximum specified. The result will be that some trigger
pulses will be missed and there will be an associated distortion (compression in the scan direction)
of the image data. When the line rate returns to or below the maximum specified, then normal
imaging will be reestablished.