WORKSHOP PAPER
Dark Current Compensation of a CMOS Image Sensor by Using In -Pixel Temperature Sensors
Abstract
In this paper a novel technique to compensate for dark current of a CMOS image sensor (CIS) by using in-pixel temperature sensors (IPTSs) is presented. The IPTSs are integrated in the same layer as the image pixels and use the same readout circuit as the pixels. Therefore, the real temperature variations in the pixel array can be measured as well as the thermal distribution across the array. The dark current compensation can be carried out locally by creating a dark reference frame from the in-pixel temperature measurements and the temperature behavior of the dark current. The artificial dark reference frame is subtracted from the actual images to reduce/cancel the dark signal level of the generated images.Keywords
CIS, in-pixel temperature sensors, dark current compensation,References
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