Year: 1991
Type: book-chapter
Abstract: The goal of perception is to extract invariant properties of the underlying \nworld. By computing contrast at edges, the retina reduces incident \nlight intensities spanning twelve decades to a twentyfold variation. In one \nstroke, it solves the dynamic range problem and extracts relative reflectivity, \nbringing us a step closer to the goal. We have built a contrast-sensitive \nsilicon retina that models all major synaptic interactions in the \nouter-plexiform layer of the vertebrate retina using current-mode CMOS \ncircuits: namely, reciprocal synapses between cones and horizontal cells, \nwhich produce the antagonistic center/surround receptive field, and cone \nand horizontal cell gap junctions, which determine its size. The chip has \n90 x 92 pixels on a 6.8 x 6.9mm die in 2μm n-well technology and is fully \nfunctional.
Authors: Kwabena A. Boahen, Andreas G. Andreou
Institutions: California Institute of Technology, Johns Hopkins University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2137609251