| 摘要 |
In an apparatus for optically detecting information signals in which light beams for reading information signals and for tracking servo-control are incident on a signal record surface of an optical record carrier through an objective lens so that respective beam spots of the light beams are formed on the signal record surface of the optical record carrier on which a signal record track is formed and a driving operation for a tracking control mirror and a detecting operation for recorded signals on the signal record surface are effected by the use of reflected light beams from the signal record surface, the improvement comprising a time base correction mirror disposed near the objective lens in an optical path of a light beam passing through the lens both on the forward way to and on the backward way from the signal record surface and the tracking mirror disposed near a light beam source, for example, a laser, the both light beams for reading the informtion signals and for the tracking servo-control passing the time base correction mirror on the forward way to and the backward way from the signal record surface and the tracking mirror only on the forward way to the signal surface. |
