contact image sensor
(kon´takt im´ij sen´s&r) (n.) Abbreviated as CIS, a type of optical flatbed scanner that does not use the traditional CCD arrays that rely on a system of mirrors and lenses to project the scanned image onto the arrays. CIS scanners gather light from red, green and blue LEDs (which combine to provide white light) and direct the light at the original document being scanned. The light that is reflected from the original is gathered by a lens and directed at an image sensor array that rests just under the document being scanned. The sensor then records the images according to the intensity of light that hits the sensor.
A CIS scanner is more compact than a CCD scanner and can be used in smaller products than CCD scanning technologies. CIS scanners also require less power than CCD scanners and often can run off battery power or the power from a USB port. CCD scanners, however, provide higher-resolution scans.