Abstract: A servo circuit performs tracking control such that the center of scanning is positioned at the center between the track from which data is reproduced and the track immediately before. Then, the beam spot scans the track from which data is to be reproduced and the immediately preceding track at the same time, and a reproduction signal made by inter-code interference between these two tracks is output. A precoding circuit performs a subtractive calculation on first data to be stored on a first track respective to second data stored on a precedent adjacent track to derive actual data to be stored on the first track and to compensate for the second data. In this way, pits or marks are formed such that inter-code interference is canceled during reproduction.

Abstract: A servo circuit performs tracking control such that the center of scanning is positioned at the center between the track from which data is reproduced and the track immediately before. Then, the beam spot scans the track from which data is to be reproduced and the immediately preceding track at the same time, and a reproduction signal made by inter-code interference between these two tracks is output. A constant relationship is maintained between data specified only by the pit or mark formed on one track and the data specified only by the pit or mark made on the former adjacent track. In this way, pits or marks are formed such that inter-code interference is canceled during reproduction.

Abstract: A servo circuit performs tracking control such that the center of scanning is positioned at the center between the track from which data is reproduced and the track immediately before. Then, the beam spot scans the track from which data is to be reproduced and the immediately preceding track at the same time, and a reproduction signal made by inter-code interference between these two tracks is output. A constant relationship is maintained between data specified only by the pit or mark formed on one track and the data specified only by the pit or mark made on the former adjacent track. In this way, pits or marks are formed such that inter-code interference is canceled during reproduction.

Abstract: A servo circuit performs tracking control such that the center of scanning is positioned at the center between the track from which data is reproduced and the track immediately before. Then, the beam spot scans the track from which data is to be reproduced and the immediately preceding track at the same time, and a reproduction signal made by inter-code interference between these two tracks is output. A constant relationship is maintained between data specified only by the pit or mark formed on one track and the data specified only by the pit or mark make on the former adjacent track. In this way, pits or marks are formed such that inter-code interference is canceled during reproduction.