| 摘要 |
PROBLEM TO BE SOLVED: To reduce the current consumption of a laser diode, and to elongate its life by turning on the laser diode in the constant scanning range of a laser beam, and turning off the laser diode in a range for changing a direction to opposite directions at the both edge parts. SOLUTION: A light emitted from a laser diode D is converged by a collimate lens 2, and turned into an almost parallel light beam. Then, the light beam is transmitted through a diaphragm 3, and turned into a further fine laser beam L by cutting the surrounding light. The oscillation of the laser beam L is synchronized with current pulses running through electromagnets M1 and M2 so that power supply to the laser diode D can be easily stopped in the neighborhood of the oscillation edge parts of the laser beam L. Then, the laser diode D is turned off in a range for changing a direction to opposite directions in which the oscillation of the laser beam L is delayed, that is, in a time when the scanning direction of the laser beam L is made opposite. The reduction of the conducting time by 20-40% can be expected. |
