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Drum scanners

Drum Scanners get their name from the glass cylinder, or drum, that the image to be scanned is mounted on.

In the middle of the drum is a light-splitting sensor which breaks the light bounced from the document in to red, green & blue components.

these color beams are sent to a photo multiplier tube or charge coupled device (CCD), where the light beam is converted to an electrical signal.

Electrical signal is then sent to monitor by a cable where we see the scanned image.

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