Contact Image Sensor

Contact Image Sensor (CIS ) ( German as contact image sensor) is an affordable, based on CMOS technology for image sensors. Mainly CIS technology was used for fax machines, but for some years now increasingly used by scanners in the lower price and quality category.

CIS are generally present as a line sensor (as opposed to surface sensors in eg digital cameras ), that is a few thousand light-sensitive points lie in a row. There is a tiny plastic lens on each of these points. The lighting is done mostly via the paralle to the sensors LEDs - for color scanners using RGB LEDs. Therefore, the naming - the sensor nearly direct contact with the sample is required for image acquisition.

The advantage of the CIS scanner over the established CCD scanners is significantly lower height and also the most cost -effective construction by eliminating a complex optics, lower power consumption, which sometimes could be lowered so that USB devices directly through the USB cable Power can be supplied.

The disadvantage of the technology lies in the extremely shallow depth of field. For templates that do not lie flat ( eg wrinkles in documents or book kinks) it therefore occurs rapidly blurring. Another disadvantage is a partially strong image noise, however, is directly related to the production quality of the sensors.

• Semiconductor device
• Microelectronics
• Image sensor