Basic analog–digital integrated circuit for edge detection based on the vertebrate retina

Novel basic analog–digital edge detection circuits in this research were proposed based on the vertebrate retina. The vertebrate retina is a pre-processor for image processing in the brain and has superior functions such as edge detection and motion detection. The proposed circuit was evaluated by the simulation program with integrated circuit emphasis (SPICE) with the 0.6 μm complementary metal oxide semiconductor (CMOS) process. The simulation results with SPICE showed that the proposed circuits can operate normally. The test integrated circuit of the unit circuit was fabricated with a 0.6 μm CMOS process. The measured results showed that the unit circuit can detect the edge position. The test integrated circuits of one-dimensional array of unit circuits were fabricated with the same process. The measured results showed that the one-dimensional circuits can detect the edge position. In the future, the realization of a new vision sensor can be expected using the proposed circuit.