| 摘要 |
PURPOSE:To form the bit/mark in a normal position by setting a bias value of a laser driving pulse current lower than usual, and delaying the light emission timing of a laser light. CONSTITUTION:A recording signal S inputted to an input terminal 1 is inputted to a delaying circuit 2 and a pulse pattern analyzing part 4. It is delayed by a prescribed time in a delaying circuit 2, and thereafter, inputted to a laser driving pulse current generating part 3, and a laser driving pulse current 10 is generated. Accordingly, a bias value of the laser driving pulse current 10, that is, a bias current value IB immediately before a rise of a pulse becomes constant. That is, an output of the laser driving pulse current generating part 3 and an output of a DC bias current generating part 6 are aligned as to the time bases by the delaying circuit 2 and inputted to an adding circuit 7, added and a laser driving pulse current 12 is generated. In such a way, a bit/mark are formed in a normal position irrespective of a pulse train of a recording signal. |
