MULTIMODE OSCILLATION SEMICONDUCTOR LASER DEVICE

摘要

PURPOSE:To provide a multimode oscillation semiconductor laser device in which the partial fluctuation of a laser beam emitted from a multimode oscillation semiconductor laser is detected and fed back to control a laser output within a required output range and, further, a partial output abnormality can be detected. CONSTITUTION:A multimode laser beam emitted from a semiconductor laser 1 is converted into a parallel beam by a collimating lens 2 and the part of the parallel beam is divided into a plurality of beams along the longitudinal direction of an ellipse along which an output fluctuates. The respective outputs of a plurality of the divided beams are detected by a line sensor 6. The summation of the detected respective beam outputs is used as a factor for feedback control and, further, the levels of the respective beam outputs are monitored to detect the output abnormality of the semiconductor laser.