IMAGE DATA COMPARISON CIRCUIT FOR RANGEFINDERS

In the particular embodiments of the invention disclosed herein, an image data comparison circuit receives digital image signal trains from two light sensor arrays of a rangefinder and compares the signals in the signal trains while they are being shifted with respect to each other. In one embodiment a set of coincidence detectors compares each signal in one signal train with all of the signals in one segment of the other image train and the number of coincidence detections by each detector is accumulated as the signal trains are cycled through corresponding shift registers. Another embodiment includes coincidence detectors for comparing all of the signals in corresponding segments of the two signal trains simultaneously.