Disk, disk device and track center detection method

An optical disk device adapted to reproduce information from an optical disk having tracks, and adapted to record information on the tracks and reproduce information from the tracks, wherein

• header regions are formed by dividing said tracks, a track center detection section is formed in each of said header regions, respectively, said track center detection section including a track center detection mark, two ID sections formed before and after said track center detection section, said two ID sections each having address information, said optical disk device comprising:
• means for focusing an optical beam onto a track of said optical disk;
• means for detecting the light beam reflected from said optical disk and transforming the light beam into an electric signal;
• means for detecting a track center signal included in said electric signal corresponding to said track center detection mark;
• and
• means for judging the tracking state of the optical beams on the track by using said track center signal.

An optical disk device adapted to reproduce information from an optical disk having tracks, and adapted to record information on the tracks and reproduce information from the tracks, wherein

• header regions are formed by dividing said tracks,
• a row of pre-pits for address information are arranged in the center line on the header regions, a wobble pit exists on at least one of the opposite sides of the center line, said wobble pits on each of the opposite sides having the same length and displaced from the center line by the same distance,
• said optical disk device comprising:
• means for focusing an optical beam onto a track of said optical disk;
• means for detecting the light beam reflected from said optical disk and transforming the light beam into an electric signal;
• and
• means for detecting a track center signal included in said electric signal corresponding to said wobble pit.

A track center detection method for detecting the track center of an optical disk having tracks and adapted to record information on the tracks and reproduce information from the tracks, wherein header regions are formed by dividing said tracks, a track center detection section is formed in each of said header regions, said track center detection section including a track center detection mark, two ID sections are formed before and after said track center detection section, said two ID sections each having address information, said track center detection method comprising the steps of:

• focusing an optical beam onto a track of said optical disk;
• transforming the light beam reflected from said optical disk into an electric signal;
• detecting a track center signal included in said electric signal corresponding to said track center detection mark;
• and
• judging the tracking state of the optical beam on the track by using said track center signal.

A track center detection method for detecting the track center of an optical disk having tracks and adapted to record information on the tracks and reproduce information from the tracks, wherein

• header regions are formed by dividing said tracks,
• a row of pre-pits for address information are arranged in the center line on the header regions, a wobble pit exists on at least one of the opposite sides of the center line, said wobble pits on each of the opposite sides having the same length and displaced from the center line by the same distance, said track center detection method comprising the steps of:
• focusing an optical beam onto a track of said optical disk;
• detecting the light beam reflected from said optical disk and transforming the light beam into an electric signal;
• and
• detecting a track center signal included in said electric signal corresponding to said wobble pit.