An Analog VLSI Velocity
نویسنده
چکیده
Jorg Kramer, Rahul Sarpeshkar and Christof Koch California Institute of Technology Computation and Neural Systems 139-74 Pasadena, CA 91125 phone: (818) 395-2874 fax: (818) 796-8876 e-mail: [email protected] ABSTRACT An integrated circuit that computes the velocity vector of a visual stimulus in one dimension is presented. The circuit combines optical sensors and associated electronics on a single silicon chip, processed with standard CMOS technology. The velocity is inferred from the time delay of the appearance of an image feature at two xed locations on the chip. The circuit operates quite robustly for highcontrast stimuli over considerable irradiance and velocity ranges. With lower-contrast stimuli the output signal for a given velocity tends to decrease, while the direction selectivity is still maintained. The individual motion-sensing cells are compact, and they are therefore suited for use in dense 1D or 2D imaging arrays.
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