Patent · US Expired

Precision measurement and positioning system for disk storage system

US4870635A · kind A · utility

16Cited by
9References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1986
Grant dateSep 26, 1989
Priority date
Expiry dateSep 19, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/5526
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The invention uses a small sized, low cost, high accuracy, semiconductor laser interferometer to position the transducer in a disc storage system. Light is reflected back over the path to be measured and directly back into the semiconductor laser. This causes the power present in the laser to be varied. Unexpectedly, the output of the photosensor associated with the laser has an asymmetric, sawtooth waveform.

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