| 摘要 |
PURPOSE:To prevent the flowing of a large current to a laser when a power source is turned ON, in an output control circuit for a semiconductor laser using a counter, by resetting the counter when the power source in a semiconductor- laser driving circuit is turned ON. CONSTITUTION:The optical output of a semiconductor laser 1 is controlled by using an up and down counter 13 in an output control citcuit for the semiconductor laser 1. When DC voltage 12V from a power source to a semiconductor driving part 17 is detected, the counter 13 is reset by a resetting circuit 19. When the DC power source to the driving part 17 is cut off and the counted value of the counter 13 is increased, the counter is reset when the power source is turned ON next time. Therefore, flowing of the large currents, when the power source to the semiconductor laser 1 is turned ON, and resultant damage of the circuit can be prevented. |
