Color aliasing free thin-film sensor array

• Published in: Sensors and actuators. A. Physical. 2006-04, Vol.128 (2), p.333-338
• Main Authors: Knipp, Dietmar, Street, Robert A., Stiebig, Helmut, Krause, Mathias, Lu, Jeng-Ping, Ready, Steve, Ho, Jackson
• Format: Article
• Language: English
• Subjects: Aliasing; Amorphous silicon; Color; Color sensor; Optical filters; Optical sensor; Sensor array; Sensor arrays; Sensors; Spectral sensitivity; TFTs; Thin-film transistors
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2006.02.007

Color information and color images are commonly captured by sensor arrays in combination with optical filters. However, the detection of the fundamental colors red, green and blue at different spatial positions of the sensors array leads to color aliasing or color moiré effects. This limitation is inherent to conventional sensor arrays using optical filters. To overcome this limitation color sensors based on vertically integrated thin-film structures were realized. The complete color information is detected at the same position of a sensor array without using optical filters. The sensors consist of an amorphous silicon ‘nipiin’-structure. The spectral sensitivity of the sensors is controlled by the applied bias voltage. The three-color sensors were integrated on top of an amorphous silicon readout electronic. The operating principle of the color sensor will be described and the performance of the color aliasing free sensor in terms of spectral sensitivity and pixel cross-talk will be discussed in this paper.