| 摘要 |
This invention provides an optical pickup apparatus which includes a plurality of light sources, a beam shaping element which is arranged in an optical path through which a light beam emitted from at least one of the light sources passes, and an optical system which includes a divergence angle conversion element and an objective lens and is arranged in an optical path through which the light beams emitted from the plurality of light sources pass, and records and/or reproduces information by condensing, through the objective lens, the light beam emitted from each light source on the information recording surface of a corresponding optical information recording medium. An almost elliptical cross-sectional shape of the light beam which enters the beam shaping element is shaped into a cross-sectional shape closer to an almost circular shape or a circular shape, and the light beam emerges from the beam shaping element. The light beam which enters the divergence angle conversion element emerges from it with a reduced angle or degree of divergence.
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