OPTICAL HEAD DEVICE
PROBLEM TO BE SOLVED: To provide an optical head device capable of accurately detecting a spherical aberration generated in a condensing optical system with respect to each standard, properly correcting the aberration, and properly recording/reproducing information in an optical disk in a compatible...
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Main Author | |
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Format | Patent |
Language | English |
Published |
10.05.2007
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Subjects | |
Online Access | Get full text |
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Summary: | PROBLEM TO BE SOLVED: To provide an optical head device capable of accurately detecting a spherical aberration generated in a condensing optical system with respect to each standard, properly correcting the aberration, and properly recording/reproducing information in an optical disk in a compatible head equipped with objective lenses of different incident pupils corresponding to a plurality of standards. SOLUTION: The optical head device corresponding to a plurality of standards includes a plurality of areas disposed in a diffracted light optical elements to diffract lights in different directions depending on wavelengths, first to third photodetectors for receiving the diffracted lights, and a control signal generation circuit for generating a control signal to drive a beam expander lens based on the detecting results of the photodetectors. COPYRIGHT: (C)2007,JPO&INPIT |
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Bibliography: | Application Number: JP20050302989 |