| 摘要 |
PURPOSE: To provide an optical pickup capable of reproducing information from two kinds of optical disks with different thickness of a prescribed part with simple constitution. CONSTITUTION: A cube 104 is turnable around a center O coinciding with an optical axis, and further, a raising mirror having reflection surfaces 104a, 104b on a surface and a back surface is provided in the oblique direction of 45 deg.. Further, the surface opposite to the disks D1, D2 between the reflection surface 104a side of the cube 104 is formed to a recessed surface shape (a concave lens 104c), and another surface is formed by a plane. The focusing position of an objective lens 106 focuses on a recording layer D2b of a t=0.6mm thickness disk D2 by approaching to the objective lens 106 side when the concave lens 104c is not arranged on an optical path, and on the other hand, the focusing position focuses on the recording layer D1b of a t=1.2mm thickness disk D1 by parting from the objective lens 106 when the concave lens 104c is arranged on the optical path. |
