OPTICAL RECORDING MEDIUM AND ITS REPRODUCER

摘要

PROBLEM TO BE SOLVED: To optimize a hologram in order to increase the soil resistance and also to improve the recognition performance for an optical medium where the hologram images are two-dimensionally aligned and recorded in the XY direction. SOLUTION: Each of diffracted light patterns R1-R3 and R5-R7 of the data holograms equivalent to 6 rows consists of (6×6) dots, and the upper left and lower right dots are used as the alignment dots 32 with the center 12 (=2+4+4+2) dots used as the areas 34 of data dots 33 respectively. In a CCD capture area 31, the patterns R1-R3 and R5-R7 of 6 pieces of data CGH 13 are aligned in (3+3) pieces of two-dimensional forms and photographed and then these patterns are recognized via a pattern recognition part.