OPTICAL INFORMATION RECORDING AND PLAYBACK APPARATUS

摘要

An optical information recording and playback apparatus for recording and playing back an optical information recording medium having a transparent protective layer comprises a tilt detection device and an off-track adding device, and includes means for determining an optimum direction in which the center of a light spot is to be displaced from the centerline of an information track on the optical information recording medium to compensate for the tilting of the optical information recording medium relative to the light beam, means for setting the amount of displacement as fixed values, and means for splitting the optical information recording medium into a number of areas and for activating a tilt detection function each time switching is made from one area to another during recording or playback. In this way, by scanning the light spot on the optical information recording medium with the center of the light spot displaced from the centerline of the information track on the optical information recording medium, the degradation of recording/playback signal quality due to the tilting of the recording surface of the optical information recording medium can be reduced.