Code disk with a plurality of tracks having different patterns
Code disk with a plurality of tracks having different patterns
Compatible optical disk
Disk-type recording medium
Information recording medium
Optical disc medium and optical disc device
Optical disk having narrow and wide guide grooves
Optical memory having narrowed track pitch
Optical recording disc
Optical recording medium
Optically readable disc with a centering member fixed to a trans
Rewritable recording medium and recording reproducing apparatus
Stamper and optical disk with specific dimensions, surface...