A 160??120 Bio-Inspired Vision Chip for Edge Detection Using a MOS-type Photodetector for Logarithmic Active Pixel Sensor

In this paper, a vision chip for edge detection based on the structure of a biological retina is introduced. The key advantage of the structure is high speed of operation. However, the charge accumulation time of a conventional active pixel sensor limits its operation speed. In order to enhance the operation speed, a logarithmic APS using a metal-oxide-semiconductor-type photodetector was applied into the vision chip. By applying a MOS-type photodetector to a logarithmic APS, we could achieve sufficient output swing for a bio-inspired vision chip. We fabricated a 160times120 bio-inspired complementary metal-oxide-semiconductor vision chip using 0.35 mum two-poly four-metal complementary metal-oxide-semiconductor technology, and then investigated.