Patent · US Expired

Optical head for optical disk recording/reproducing apparatus including modified Wollaston prism

US5189655A · kind A · utility

28Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 11, 1990
Grant dateFeb 23, 1993
Priority date
Expiry dateSep 11, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B11/10541
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical head, for an optical disk recording/reproducing apparatus, for irradiating a recording medium by a light beam emitted from a light source and introducing an information light formed by a light beam reflected from the recording medium to a photo detector, a shift of an optical axis of the information light being minimized. The optical head includes a unit for receiving the information light which is reflected from the recording medium, a first reflecting unit for reflecting such information light, a second reflecting unit for reflecting the information light reflected by the first reflecting unit and for directing the reflected information light toward the photo detecting system, and a unit for emerging the information light reflected by the second reflecting unit to the photo detecting system. The first reflecting unit has a surface for reflecting the information light thereby, and the second reflecting unit also has a surface for reflecting the reflected information light from the surface of the first reflecting unit. The surface of the first reflecting unit is substantially parallel to the surface of the second reflecting unit. The emerging surface has a surface from w…

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