Patent ID: 7689104

Claim:
A recording/playback device comprising: an information conversion unit converting video or audio information, received from an external source, to video or audio data for recording on an optical disk having at least two recording layers; a recording unit recording the video or audio data on said optical disk; and a playback unit playing back the video or audio data recorded on said optical disk, wherein said optical disk has a plurality of recording zones, each recording zone as a unit of recording includes said recording layers and, the recording unit records the video or audio data sequentially, one recording zone at a time, in two or more recording layers of recording zone, and after the video or audio data is recorded, if in one of the recording zones, a part of the video data or audio data recorded in said recording zone is erased logically, the device moves at least a part of the video or audio data left unerased in said recording zone to a different layer or a different recording zone so that a number of layers, occupied by the video or audio data left unerased, is reduced in said recording zone.