| 摘要 |
PURPOSE:To make a sufficiently reliable address part only exist by reproducing an address which lowers a sensitivity from a reproducing address signal, comparing with a sector address, and a t the time of dissidence, preventing to reproduce completely the address part. CONSTITUTION:Respective sectors are composed of an address part 1 where an address signal is recorded. When a certain sector is inspected, a sector address 13 is sent to a recording reproducing part 10 by a control part 6. From a reproducing address signal 17 when the address part 1 is reproduced, a binary level is changed, an address in which the reproducing sensitivity is lowered is reproduced and this is compared with the sector address 13 by a decoder 8. At the time of dissidence, a prescribed signal is written in layers at the address part 1 and the address part 1 can not be reproduced. For this reason, the address part only having a sufficient relability can be made to exist at an optical disk. |
