A Wide Dynamic Range CMOS Image Sensor with an Adjustable Logarithmic Response
نویسندگان
چکیده
A wide dynamic image CMOS image sensor with a user adjustable logarithmic photo-response is presented. A pMOS switch and a time-dependent reference voltage are integrated into a three-transistor (3T) pixel structure to implement a logarithmic response. Several pixels have been manufactured using a 0.25μm standard CMOS technology. Compared to the conventional logarithmic response pixel based on a diode-connected transistor, the proposed pixel combines a wide dynamic range of 120dB with much higher responsivity (250mV/decade) and better dark response.
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