| 摘要 |
PROBLEM TO BE SOLVED: To easily and precisely performe the adjustment of optical parts without increasing the number of parts by providing the reflection surface to a portion of the incident surface of the collimating lens, which converts the laser beams emitted from a semiconductor laser element into collimated light beams, so as to reflect a portion of the laser beams to the light emitting point of the laser. SOLUTION: If a collimating lens 107 is mounted onto the position, which is designed, without any tilt, a reflection surface 110 reflects outer peripheral section beams 109 of diffused beams 106, which are emitted from the laser light emitting point of a laser chip 104, and the beams 109 are formed so that the beams 109 are returned to the laser emitting position. The reflected beams 109 return to the chip 104, optical noise is generated and a photodiode 105 detects the noise. The fine adjustments of the tilt and the position of the lens 107 are conducted so that the returned optical noise becomes a maximum. Thus, the lens 107 is easily set to a correct designed position. |
