PUB - Publikationen an der Universität Bielefeld

Color images are commonly captured with sensor arrays covered with a mosaic of rgb-filters. Hence one-chip color imagers (CMOS and CCD color cameras) suffer from color aliasing or color moire effects. In order to overcome these limitations color sensors based on vertically integrated diodes were realized. The complete color information of the color aliasing free sensor can be detected at the same spatial position without using additional optical filters. The color separation is realized by the wavelength dependent absorption of the incorporated material in the depth of the devices. A promising material for sensor application in the visible range is amorphous silicon and its alloys. Thin film systems based on amorphous two terminal and stacked multi terminal devices are fabricated by a low temperature CVD process. The spectral sensitivity of the sensors can be controlled by the optical and optoelectronic properties of the materials on one hand and the design of the devices on the other hand. The operation principle of the sensors will be presented and the different detection concepts will be compared regarding their application in the field of color recognition and digital imaging.