| 摘要 |
An optical pick-up device for optically recording and/or reproducing information on an information record medium having plural record layers and guide tracking layers in the depth direction is disclosed. The optical pick-up device for optically recording and/or reproducing information on an information record medium having plural record layers and guide tracking layers in the depth direction comprises a first light source for radiating first light beam, a second light source for radiating second light beam which is different from the first light beam, plural objective lenses selectively arranged in a common optical path for the first light beam and the second light beam, for focusing first light beam and second light beam with different spot spacing, objective lens selection means for selecting objective lens arranged in a common optical path of plural objective lenses according to depth position of desired record layer to be recorded and/or reproduced of the information recording medium, thereby focusing the first light beam on the guide track layer through the objective lens arranged in the common optical path, and focusing the second light beam on the desired record layer.
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