| 摘要 |
An objective lens apparatus is disclosed. The apparatus includes: a first objective lens with a first numerical aperture, which is capable of focusing a laser light on a first optical record medium with a first cover layer of a first thickness; a second objective lens with a second numerical aperture smaller than the first numerical aperture, which is capable of focusing the laser light on a second optical record medium with a second cover layer of a second thickness larger than the first thickness; a third objective lens with a third numerical aperture smaller than the second numerical aperture, which is capable of focusing the laser light on a third optical record medium with a third cover layer of a third thickness larger than the second thickness; and a lens holder which holds the first objective lens, the second objective lens, and the third objective lens.
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