| 摘要 |
PURPOSE:To attain a high accurate positioning and to attain the stable track alignment even to a temperature change, etc., by providing N-1 semiconductor lasers in which a light emitting point position is variable in the active layer direction of the semiconductor laser, in a light head to irradiate N number of light spots to an information recording medium and record or reproduce the information. CONSTITUTION:By having N semiconductor lasers and using N-1 semiconductor lasers in which a light emitting point position can be changed in a laser emitted active layer direction, the light emitted point position changing direction of the semiconductor lasers is set to the track direction and the vertical direction. Namely, the laser lights emitted from a light emitting point 2 of a first semiconductor laser 1 are image-formed as a fine spot 5 onto a track 4 on the optical disk by a focus lens 3 and the one side electrode of a second semiconductor laser 6 is divided into two stripe electrodes 7 and 8. Consequently, when an injection current distribution to the semiconductor laser 6 is made non- symmetrical by a volume 10, a spot 13 can be positioned onto the track 4. Thus, adjustment is simple and dislocation is hard to occur even due to the temperature change, etc. |
