| 摘要 |
PROBLEM TO BE SOLVED: To make a read easy when additional information is recorded by a hologram. SOLUTION: Radially plural CGH arrays 3a (3b) are recorded concentrically at equal intervals. The CGH arrays 3a (3b) are composed of, for example, three arrays in a disk radial direction; and the center array among the three arrays is a control CGH array 3-1 for determining read timing and the two arrays on both the sides are information CGH arrays 3-2 representing additional information such as disk identification information and copyright information. In another example, the center array is an information CGH array 30-2 and the two arrays on both the sides are control CGH arrays 3-1. |
