| 摘要 |
PURPOSE:To enable rear section specular coating and cleavage, and to improve performance by extracting beams from a side surface in the rectangular direction to a resonant optical axis of an active layer or a wave guide layer in a semiconductor laser element and supplying a photodetector with said beams. CONSTITUTION:With a semiconductor laser element 1, a resonator is formed by resonator specular surfaces 4a, 4b, it is oscillated by currents flowing between a power supply terminal 7 for drive and a common electrode 9, and oscillation beams are wave-guided by an active layer 6 and an optical guide layer 3 optically coupling with the active layer 6. One part of beams is converted into a radiation mode by a projecting section 10 formed to the optical guide layer 3 at that time, and emitted toward a photodetector 2. |
