Patent · US Expired

Telecentric rotary actuator in an optical recording system

US5422872A · kind A · utility

32Cited by
12References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 8, 1993
Grant dateJun 6, 1995
Priority date
Expiry dateMar 8, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/1378
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A telecentric rotary actuary in an optical storage system. A laser generates a laser beam which is focused by an objective lens onto an optical disk in order to write data to and read data from the optical disk. In performing a seek, a galvo rotates a mirror in order to reflect the laser beam to different radial displacements in reference to the optical disk. The position of the laser beam is detected, and a rotary actuator, to which the objective lens is attached, follows the movement of the laser beam. A telecentric optical system comprising a relay lens and an image lens is used to minimize an offset between the laser beam and the objective lens. The relay lens focuses the laser beam to a back focal point. The image lens optically conjugates the back focal point to a front focal point corresponding to the objective lens in order to demagnify any offset.

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