| 摘要 |
PURPOSE:To attain high density of a disc and to quicken the access speed by controlling the reproducing speed the disc divided into plural divisions in the rotating direction and recorded in different number of revolutions at each division while changing over plural reference values corresponding to each division. CONSTITUTION:A data recorded on the disc 1 is read by a pickup 2 and processed by a signal processor 3. On the other hand, as to the reproducing position of the disc 1, a signal representing the reproducing position is fed to a feeding controller 5 from a microcomputer 4 to control a feeding motor 7. The number of revolutions of the disc 1 is divided, e.g., into five divisions in the rotating direction and the signal is recorded with the number of revolutions decreased toward outer circumference of the disc. When the microcomputer 4 decides the position to be accessed, a voltage proportional to the number of revolutions is generated by a variable reference voltage 10, a rotating motor 8 is controlled by a number of revolution controller 6. Then, the disc 1 reaches an objective number of revolutions and the data is read immediately. Thus, the high density recording of the disc is attained and the access speed is increased. |
