A 1k x 1k high dynamic range CMOS image sensor with on-chip programmable region-of-interest readout

An integrated 1024x1024 CMOS image sensor with programmable region of interest (ROI) readout and multi-exposure technique has been developed and successfully tested. Size and position of the ROI is programmed based on multiples of a minimum readout kernel of 32x32 pixels. Since the dynamic range of the irradiance normally exceeds the electrical dynamic range of the imager that can be covered using a single integration time a multiexposure technique has been implemented in the imager. Subsequent sensor images are acquired using different integration times and recomputed to form a single composite image. A newly developed algorithm performing the recomputation is presented. The chip has been realized in a 0.5µm n-well standard CMOS process. The pixel pitch is 10µm x 10µm and the total chip area is 164mm².