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Both the active column sensor (ACS) pixel sensing technology and the PVS-Bus multiplexer technology have been applied to a color imaging array to produce an extraordinarily high resolution, color imager of greater than 8 million pixels with image quality and speed suitable for a broad range of applications including digital cinema, broadcast video and security/surveillance. The imager has been realized in a standard 0.5 μm CMOS technology using double-poly and triple metal (DP3M) construction and features a pixel size of 7.5 μm by 7.5 μm. Mask level stitching enables the construction of a high quality, low dark current imager having an array size of 16.2 mm by 28.8 mm. The image array aspect ratio is 16:9 with a diagonal of 33 mm making it suitable for HDTV applications using optics designed for 35 mm still photography. A high modulation transfer function (MTF) is maintained by utilizing micro lenses along with an RGB Bayer pattern color filter array. The frame rate of 30 frames/s in progressive mode is achieved using the PVS-Bus technology with eight output ports, which corresponds to an overall pixel rate of 248 M-pixel per second. High dynamic range and low fixed pattern noise are achieved by combining photodiode pixels with the ACS pixel sensing technology and a modified correlated double-sampling (CDS) technique. Exposure time can be programmed by the user from a full frame of integration to as low as a single line of integration in steps of 14.8 μs. The output gain is programmable from 0dB to +12dB in 256 steps; the output offset is also programmable over a range of 765 mV in 256 steps. This QuadHDTV imager has been delivered to customers and has been demonstrated in a prototype camera that provides full resolution video with all image processing on board. The prototype camera operates at 2160p24, 2160p30 and 2160i60.
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