Reduction of Fixed Pattern Noise in Bolometer-type Uncooled Infrared Image Sensors Using Pixel Current Calibration Technique

摘要

In this paper, we propose a pixel current calibration technique for reducing the fixed pattern noise due to the deviations in the bolometer resistance. Usually, it is difficult to calibrate the fixed pattern noise of a bolometer array. The principle of the pixel current calibration technique is that the dark current of a reference pixel is subtracted from the dark current of each active pixel. To reduce the difference in current due to the pixel resistance variation, a suitable calibration current is required. Through this pixel current calibration technique, the dark current of the active pixel resistor, and subsequently, the fixed pattern noise, can be reduced significantly. A readout circuit using the proposed pixel current calibration technique is simulated and fabricated using the 0.35 μm standard CMOS process.