| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical pickup capable of reducing the number of parts, reducing the cost and being miniaturized in a pickup in which a disk having first recording density is compatible with a disk having second recording density. SOLUTION: In the optical pickup having a first light source 2 emitting a first laser beam L1 for recording/reproducing an optical disk having a first recording density, a second light source 12 emitting a second laser beam L2 for recording/reproducing an optical disk having a second recording density lower than the first recording density, and a polarizing beam splitter 8 having a polarizing film 8A in the internal part in order to synthesize the optical axis of an optical system advancing from the first light source to the optical disk and the optical axis of an optical system advancing from the second light source to the optical disk on the same optical axis, an optical part 46 operating as the condensing lens of the optical system of the backward path of the first laser beam is served also as the collimator lens or the NA exchange lens of the optical system of the forward path of the second laser beam. Thus, the number of part is reduced, the cost is also reduced and miniaturization is realized in the pickup in which the disk having the first recording density is compatible with the disk having the second recording density. |
