PROCEEDINGS ARTICLE | May 15, 2001
Proc. SPIE. 4306, Sensors and Camera Systems for Scientific, Industrial, and Digital Photography Applications II
KEYWORDS: Clocks, Capacitors, Imaging systems, Image processing, Video, Amplifiers, Cadmium sulfide, Charge-coupled devices, Multiplexers, Laser imaging
A family of monochrome, high-speed linear imagers has been developed with each device to be available as a single chip fabricated using a standard commercially available CMOS process. Currently, the 2048 pixel device has been fabricated using a 0.5-micron CMOS process and its architecture, functionality and performance is described. The family of imagers features a unique combination of high functional integration, very high speed, low dark current, high sensitivity and high pixel-to-pixel uniformity. The pixels are 7.0 microns by 7.0 microns and have 100 percent fill factor. The high pixel-pixel uniformity is made possible by using low dark current pixels, a correlated double sampler circuit per pixel and a fully differential video bus. High functional integration is enabled by on-chip logic that is provided to minimize support circuitry and simplify application. Included are several exposure modes that provide full-frame electronic shutter, independent control of integration time and simultaneous integration and read-out. Only 5 volts DC and clock signal running at twice the desired pixel rate are required for basic operation. Low dark current and high sensitivity result from a novel pixel and low-noise preamplifier structure. A novel video multiplexing structure provides the very high read-out speed of 60 Mpixel/sec per 2048 pixel segment while sustaining an MTF of 50 percent at 35 line pairs per millimeter.
