Intelligent Automation & Soft Computing · 2006 · 11 citations · 0 references
EngineeringBiomedical EngineeringAnalog ElectronicsVisual NeuroscienceVisual PerceptionAnalog Integrated CircuitsAnalog IntegrationDigital Image ProcessingEdge DetectionImage ProcessingVisual SystemAnalog Circuit DesignBionic Vision SystemsCmos Analog Circuit DesignCmos Image SensorsDynamic RangeLight IntensityRetinal Image ProcessingVisual Signal Processing
Abstract An analog circuit for edge detection was proposed based on vertebrate outer retinas. The chip which contained 40 × 40 unit circuits in a two-dimensional array was fabricated with 0.35 μm CMOS process. Edge images were experimentally observed in a brightness range over 3 orders of magnitude. It was clarified by simulation with the simulation program with integrated circuit emphasis (SPICE) that a wide dynamic range of light intensity over 6 orders of magnitude could be realized by replacing a nonlinear register with a linear register in the fabricated chip.