Patent · US Expired

Optical element, optical head using the optical element, and optical recording and reproducing apparatus using the optical element

US6480454B1 · kind B1 · utility

21Cited by
9References
44Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 1999
Grant dateNov 12, 2002
Priority date
Expiry dateDec 13, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2203/18
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The invention presents an optical element that has a good correcting effect with regard to aberrations and is easy to manufacture, as well as an optical head and an optical recording and reproducing apparatus using the same. The optical element includes a first substrate, a second substrate arranged substantially in parallel to the first substrate, a voltage applying electrode arranged between the first substrate and a liquid crystal, an opposing electrode arranged substantially in parallel to the voltage applying electrode and opposing the voltage applying electrode, and a liquid crystal arranged between the first substrate and the second substrate. By changing the voltage between the voltage applying electrode and the opposing electrode, the phase of the light incident on the liquid crystal can be changed.

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