optical reading device for reading the movable nosnika information, especially for reading video cds

摘要

An optical read unit for reading radiation-reflecting video discs comprises a semiconductor laser which with the aid of a scan wobbler and a focussing wobbler is moved at high frequency in two directions relative to the video disc, a radial direction for tracking purposes and a direction normal to the disc for the purpose of automatic focussing. The semiconductor diode laser is mounted on a metal radiation source carrier which is connected to a heat sink for carrying off the heat with a low temperature gradient, and is driven by piezo-electric plates.