Optical encoder
US6774355B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 25, 2002 |
| Grant date | Aug 10, 2004 |
| Priority date | — |
| Expiry date | Sep 20, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/36
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical encoder of the present invention includes a scale movable in a preselected direction and formed with an array of slits in the direction of movement of the scale. A light source emits a light beam toward the scale. A light-sensitive portion transforms light transmitted through or reflected from the scale to a corresponding electric signal. The slits each have a dimension, as measured in the direction perpendicular to the direction of movement of the scale, limited in accordance with the diameter of a beam spot to be formed on the scale. With this configuration, the encoder is low cost and can correct the mounting error of the scale without resorting to precise adjustment at the time of mounting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.