| 摘要 |
PURPOSE:To prevent instability of an oscillating stage due to the returned light from a video disc, by forming the second grooves, which constitute the secondary gain regions, in the vicinity of the first groove that constitutes a laser oscillating region. CONSTITUTION:In a laser device, which is used in a video disc, a first groove 6 in a stripe shape is formed at the center of a first semiconductor layer 2, and a laser oscillating region is provided. Meanwhile, second grooves 7, whose four sides are blocked, are formed on both sides of the first groove 6 in parallel in a symmetrical pattern. The secondary grooves 7 constitute the secondary gain region. Naturally emitted light, whose spectral width is wide, and which is generated in said secondary gain region, is injected to the laser oscillating region 6. Then the longitudinal-mode spectraum in the laser oscillation becomes a multiple mode. Therefore the operation can be stabilized with respect to the returned light. |
