Trigger, Reset and Strobe in Line-Scan
In order to ensure the terminology consistency throughout the MultiCam documentation, the following conventions have been taken.
A trigger pulse is an electrical signal sent by the external system to synchronize the line rate of the camera to some external reference. This is needed to preserve the geometric aspect of a line-scanned object moving at a non-uniform speed. The trigger pulse is often referred to as a line trigger pulse, although the rate conversion feature results in a trigger frequency that may not be equal to the camera line frequency.
A page trigger pulse is an electrical signal sent by the external system to instruct a frame grabber to perform the acquisition of a set of several successive lines. This is usually used when a moving object is about to enter the field of view of the line-scan camera.
In the case of line-scan, an adjacent set of scanned lines is called a page. The name page is borrowed to the document scanning application, and has been chosen to denote the case of line-scan cameras. The area-scan corresponding item is a frame. The length of the page is chosen to adequately cover the extension of the moving object.
Due to the similarities of the frame and page concepts, a page trigger is sometimes referred to as a frame trigger. The line-scan or area-scan context makes the difference.
A reset pulse is an electrical signal sent by the frame grabber to instruct a line-scan camera to start its line acquisition cycle. The reset pulse is often referred to as a line reset pulse.
Terminology conventions in line-scan