| 摘要 |
An optical pickup that is compatibly utilized having a high optical efficiency and an optical recording and/or reproducing apparatus including the optical pickup includes a light source, a polarization beam splitter to transmit or to reflect an incident light beam according to a polarization direction of the incident light beam, a quarter wave plate to change the polarization direction of the light beam that passes through the polarization beam splitter, a holographic optical element formed of an anisotropic material and including a diffraction pattern to transmit or to diverge the light beam that passes through the quarter wave plate according to the polarization direction of the beam, and an objective lens to focus a first polarized beam component that is transmitted directly through the holographic optical element onto the first information storage medium with a first numerical aperture (NA), and to focus a second polarized beam that is diverged by the holographic optical element onto the second information storage medium with a second NA.
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