OPTICAL SYSTEM FOR MONITORING OUTPUT OF OPTICAL PICKUP DEVICE, AND OPTICAL PARTS

摘要

PROBLEM TO BE SOLVED: To provide an optical system for monitoring outgoing light and optical parts in which adjustment can be performed simply and the outgoing light from a laser diode can be separated in a desired level without providing a specific polarization separation characteristic for a polarization separation film of a polarizing beam splitter, also, without attaching accuracy of the laser diode and optical axis direction accuracy of a wavelength plate.

SOLUTION: In an optical system device for monitoring the quantity of the outgoing light of a light source of an optical pickup device, this device is provided with an optical retardation plate of which the optical retardation Δ is 0°<Δ<180° or 180°<Δ<360°, and which is arranged in the direction of the optical axis of approximately 45° for a polarization plane of the linear polarization light emitted from the light source, and a polarization separating means reflecting most of the first polarization components being vertical to a forward direction of the laser beam emitted from the light source, and transmitting most of the second polarization components intersecting orthogonally to the first polarization components.

COPYRIGHT: (C)2004,JPO