Video clock signal generator in an optical scan type image input device

摘要

A video clock signal generator comprises: means (2) for supplying a light beam; a mask (9 having opposite ends spaced by a predetermined distance; a vibration scanner (5) for reflecting the light beam and forming a light spot vibrating on the mask beyond the opposite ends thereof; a detector (7) for generating an output signal representing optical information from the mask; a counter (15) for counting a time required for the light spot to cross the opposite ends of the mask based on the output signal of the detector; and a control unit (16) for controlling an amplitude of the scanner mirror in accordance with the time counted by the counter.