| 摘要 |
PURPOSE:To enlarge the length of a resonator, and to reduce a threshold current by a method wherein the resonator is constructed of both the edge faces and a diffraction grating of a semiconductor laser. CONSTITUTION:When current is supplied between a first and a second electrodes 1, 18, carriers are injected in an active layer 5 to generate light. Out of generated light, only the light corresponding to the period of a diffraction grating applied to a guide layer 7 is amplified to generate a laser oscillation. The laser beams are led out from both the edge faces 11, 12, while when the diffraction grating is an even number order, the laser beam is radiated also to the vertical direction to the layer 15 like the laser beam 13. A clad layer 9 is transparent to the laser beam. Because a contact layer 10 is not formed to a laser beam take-out part 19, the laser beam 13 radiated to the direction vertical to the layer 5 becomes easily transmitted, and the beam can be led out to both the directions. |
