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Reflected light from the record in an optical disc player is directed at a string of photo sensitiv diodes (18). Two adjacent diodes (e.g. 18i, 18i+l) of this string of diodes receive light from a selected portion (28) of the track on the disc. The outputs of these two adjacent diodes are summed together to generate the output signal (Vout) for the optical disc player. The outputs of the two diodes are also subtracted from one another to generate a differential signal (VD) for tracking purposes. The magnitude of this differential signal is a measure of the relative magnitudes of the signals on the two adjacent diodes and therefore is an indication of the position of track laterally of the diodes. When this differential output becomes larger than a preset value, a control logic circuit (26) showing that the two diodes are no longer receiving the reflected light, responds by changing the combination of two adjacent diodes in the string which receive the reflected light, and generate the video output signal and the difference signals.