Patent · US Expired

Absolute encoder utilizing a code pattern carrier having a varying mixture of phosphors deposited thereon

US7462815B2 · kind B2 · utility

5Cited by
6References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 2005
Grant dateDec 9, 2008
Priority date
Expiry dateFeb 15, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D5/34715
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An encoder having a code carrier, light source, and detector is disclosed. The code carrier includes a track that emits light at each of a plurality of track points on the track when that track point is illuminated with light having a predetermined spectrum. Each of the track points emits light having a spectrum that is different from the spectrum emitted by others of the track points. The light source illuminates a portion of the track with light of the predetermined illumination spectrum. The detector provides a plurality of signals indicative of the spectrum of light leaving the portion of the track when the portion includes one of the track points. The code carrier moves with respect to the detector, and the signals define the relative position of the code carrier with respect to the detector.

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