Patent · US Expired

Optical pickup apparatus

US6781947B2 · kind B2 · utility

2Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 20, 2001
Grant dateAug 24, 2004
Priority date
Expiry dateJul 16, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/0006
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Laser beams h1, h2 with different wavelengths emitted from semiconductor lasers 2a, 3 are incident to an optical path joint prism 13 and each of optical intensities of the laser beams h1, h2 is detected by a photoelectric conversion element 15 provided in an optical path integrated by the optical path joint prism 13 on which a semi-transmission film HM is provided and APC control of each of light emission intensities of the semiconductor lasers 2a, 3 is performed on a basis of each of detection results. As a result of this, the beam intensity of the laser beam h1 passing through the optical path joint prism 13 to be applied to an information recording medium and the laser beam h2 reflecting the optical path joint prism 13 to be applied to the information recording medium are controlled properly.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.