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MultiCam Boards Documentation > MultiCam Documentation > MultiCam User Guide > General Topics > Line-Scan Inspection Topics > Exposure Issues
Exposure Issues

Some additional knowledge on the way the CCD sensor operates is needed to understand the goals of the camera control means offered by MultiCam.

In order to build an electrical signal representing the light intensity of a point, the CCD pixel area should be exposed to the light during a certain amount of time. This amount of time is known as the exposure time, or the integration time.

In a line CCD sensor, all the pixels experience simultaneously the exposure period. This means that the exposure starting and stopping instants are common to all pixels.

Two cases are to be considered:

All line-scan cameras support the permanent exposure scheme.

Not all line CCD sensors and not all line-scan cameras are able to support the controlled exposure scheme.

In order to support the controlled exposure scheme, a line-scan camera should be fitted with a so-called electronic shutter feature.

As this will become clear later in the document, the industrial vision integrator will prefer a line-scan camera equipped with the electronic shutter.