Patent · US Expired

Optical head apparatus

US5886978A · kind A · utility

11Cited by
4References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 26, 1996
Grant dateMar 23, 1999
Priority date
Expiry dateSep 26, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/0935
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical head apparatus is realized in which an objective lens actuator and the whole optical system are reduced in height, and which can be used in common between a system in which the light beam comes incident in the direction of the radius of the information disk and another in which the light beam is arranged in a direction tangent to the information disk. A lens holder having a substantially hexagonally shaped plane is supported by two wire springs, each shaped in a triangle with two of its aides extended and fitted to an actuator base, to be able to freely move up and down and to freely rotate. On two side walls of a lens holder are arranged tracking coils and focusing coils, and magnets are arranged in opposite positions of the actuator base. Underneath an objective lens is arranged an opening wide in the horizontal direction, and the dimension of the apparatus in the vertical direction (the direction normal to the surface of the diagram) can be reduced by arranging a 45-degree mirror in this space not in contact with the lens holder.

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