The manner which generates the security mark on the optical data carrier, the optical data carrier, the read-out device which reads out manner, and the security mark which read out the device and the security mark which generate the security mark, holographic storage

摘要

The device comprises directing means (8a, 8b, 11) for directing a first and a second light beam (7, 6) onto a hologram area (10) of the optical data carrier (1), wherein the first and second light beams (7, 6) are coherent light beams. The directing means (8a, 8b, 11) are adapted to direct the first light beam (7) onto the hologram area (10) along a first direction, and the second light beam (6) onto the hologram area (10) along a second direction. Tilting means (12) are provided for tilting the second direction by a predefined tilt angle with respect to the first direction.