Fax machine CIS

CIS uses a contact-type image sensor (photosensitive sensor) for sensitization. At the scanning platform one to two millimeters, a row of 300-600 closely spaced red, blue and green LED sensors The light is mixed together to generate a white light source, which replaces the CCD array, lens, fluorescent tube, or cold cathode ray tube in a CCD scanner. The variable CCD scanner is a CIS scanner (optical, mechanical, and electrical). Electric one. The working principle of the CIS product is very similar to that of a facsimile machine. It does not have a lens assembly, and the CIS photosensitive device spans the entire scanning width of the web, and is maximally close to the original. CIS uses light-emitting diodes as light sources and diode sensing elements. The structure is simple and compact, so the volume can be made very small. The thickness of CIS products is usually less than half that of CCD products. However, since the CIS device does not have a lens imaging portion, the depth of field is very small and it is generally only possible to scan planar objects. CIS devices are semiconductor devices that can achieve lower costs after mass production. However, CIS technology is still in the development stage, and its optical resolution is generally only 300 x 600 dpi. Compared with CCD, CCD scanning technology uses optical imaging devices to scan the image with very uniform color and brightness, and because of the high brightness light source, it can achieve very high color resolution. The CIS technology uses a large area of ​​photosensitive devices, it is still difficult to ensure the uniformity of the scan, and because the use of a lower brightness diode light-emitting devices, so the color resolution of CIS is not as good as the CCD.