Patent · US Expired

Optical information processing device

US4760568A · kind A · utility

14Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 25, 1986
Grant dateJul 26, 1988
Priority date
Expiry dateSep 25, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/124
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical head for a laser memory disk in accordance with the present invention comprises: a substrate (1); a waveguide layer (3) formed over a main surface of the substrate; a semiconductor laser (4) for injecting laser beams into the waveguide layer, the semiconductor laser being set in a hollow (17) dug down at least into the waveguide layer; a focusing grating coupler (6) formed on the waveguide layer for focusing the injected laser beams on the memory disk and introducing beams reflected back from the disk into the waveguide; beam splitter means (5) formed on the waveguide layer between the semiconductor laser and the focusing grating coupler, for bisecting each of the reflected beams at a prescribed acute angle; and photodetector means (10) for converting the bisected beams into electrical signals, the photodetector means being provided along both the sides of the semiconductor laser and situated not nearer to the focusing grating coupler as compared with the semiconductor laser.

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