| 摘要 |
PURPOSE:To evade deterioration of a light source and to attain the even record states at each record position by changing the bias electric power not the peak electric power of the light source at each record position in the radius direction of a recording medium. CONSTITUTION:When the information is recorded on an optical disk 1, a movable contact pieces S0 of a switch circuit SW is set at either one of fixed contacts S5-S2 by a CPU23. In this case, the bias electric power is increased toward the outer circumference of the disk 1. When a record signal is supplied from a laser control circuit 14, transistors TR1 and TR2 work to actuate a semiconductor laser 9. Thus a recording state is set. In this case, a TR3 changes the base potential of the TR2 based on the level of a bias current so that the peak value of the record signal has no change despite the switch of the bias electric power. |
