| 摘要 |
An optical pickup device includes a beam shaping mirror. The mirror has a first optical surface on which a wavelength selection film and a diffraction grating are formed, and a second optical surface that is composed of a reflecting surface. The wavelength selection film passes a first laser beam and reflects a second laser beam. A light intensity distribution of the first laser beam is converted from an elliptic shape to a circular shape by operation in which the first laser beam which passes the wavelength selection film and is input to the beam shaping mirror, is reflected on the second optical surface, passes the wavelength selection film and is output from the mirror. The second laser beam is diverged by the diffraction grating. Directions of the first and second laser beams which are output from the mirror are made the same by diffraction of the second laser beam.
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