OPTICAL PICKUP AND OPTICAL DISK DRIVE

摘要

PROBLEM TO BE SOLVED: To provide an optical pickup capable of reliably deciding the number of layers of an optical disk and to provide an optical disk device.

SOLUTION: The optical pickup includes: a polarization optical element 18 having respective boundary surfaces at front and rear parts separated by a prescribed distance from a focused point on which focused light reflected by a focused recording layer in reflection light beams is condensed by a condenser lens 17 on the surface including optical axes of the reflection light beams condensed by the condenser lens 17 and changing the polarization direction of stray light contained in the reflection light beams by reflecting only the stray light reflected by a non-focused recording layer in the reflection light beams; a separating means 20 in which a reflection light beam emitted from the polarization optical element 18 is made incident and which separates focused light and stray light contained in the reflection light beam on the basis of its polarization direction; and a stray light detecting means 25 having a plurality of light receiving regions for detecting the light quantity of the stray light separated by the separating means 20.

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