Patent · US Expired

Optical pickup

US4824191A · kind A · utility

17Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 28, 1988
Grant dateApr 25, 1989
Priority date
Expiry dateMar 28, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/1372
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical pickup for reading out information from an information recording media, such as an optical diskette, comprises a light source for irradiating light beam onto an optical diskette, an optical sensor for detecting the light beam reflected at the optical diskette, and an optical system including a wave plate and two hologram lenses. The first hologram lens diffracts the light beam from the light source, and the second hologram lens transmits the same light beam. On the other hand, the second hologram lens diffracts the reflected light beam from the optical diskette toward the optical sensor, and the first hologram lens transmits the same reflected light beam.

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