Bio-inspired analog circuitry model of insect photoreceptor cells

Copyright © 2006 SPIEThis paper describes the implementation of a robust adaptive photodetector circuit that mimics the characteristics of insect photoreceptors. The implementation of the photodetector circuit is an elaborated version of the mathematical model initially developed by van Hateren and Snippe. It consists of a linear photodetector, two divisive feedback loops and a static non-linearity stage. The photoreceptor circuit was rigorously tested under both steady-state and dynamic (natural scenes) conditions and the circuit parameters optimized such that the output was highly correlated to results obtained from fly photoreceptors observing an identical stimulus. The results show that this adaptive non-linear photoreceptor circuit is ideally suited to mimic the biological photoreceptors found in insects