| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical element having a beam shaping function constituted so that the performance of anamorphic lens can be prevented from being deteriorated even when a fluctuation of wavelength is generated. SOLUTION: In the optical element constituted of an anamorphic lens 11 having a beam shaping function having different focal distances in a direction vertical to the direction in parallel with the active layer of the semiconductor laser 10 for turning lights from a semiconductor laser 10 into almost parallel lights, the anamorphic lens 11 is integrally constituted of plural materials 12 and 13, and at least the first face and final face (third face) of the anamorphic lens 11 is formed like an aspheric shape. Thus, it is possible to realize an optical element (collimate lens for shaping beams) whose wavefront deterioration is small against wavelength fluctuation by allowing the optical element to have an achromatic action. |
