Process and device for controlling an incident optical beam for reading a track of information on a dynamic medium

摘要

A process and device are provided for controlling an incident optical beam for reading a track of a dynamic medium, e.g. a digital disc, having information stored therein. The beam reflected by the disc is picked up by an optical pickup having several photodetectors and the positioning error of the beam with respect to the track is determined from elementary signals delivered respectively by the photodetectors and from an overall signal containing the information and delivered by the pickup.