Patent · US Expired

Optical element, optical head, optical recording reproducing apparatus and optical recording/reproducing method

US6987598B2 · kind B2 · utility

3Cited by
22References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 14, 2004
Grant dateJan 17, 2006
Priority date
Expiry dateJul 14, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/0013
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The invention presents an optical element with which an optical head can be configured, in which there is little deterioration of the correctional effect when the objective lens shifts, as well as an optical head and an optical recording/reproducing apparatus using such an optical element. The invention also presents a novel optical recording/reproducing apparatus and optical recording/reproducing method. The optical element, includes a first voltage application electrode 13, a first opposing electrode 17 arranged in opposition to the first voltage application electrode 13, and a first phase changing layer 15 arranged between the first voltage application electrode 13 and the first opposing electrode 17. By changing a voltage between the first voltage application electrode 13 and the first opposing electrode 17, a phase that converts plane waves into spherical waves is imparted on light that is incident on the first phase changing layer 15.

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