Optical rotary encoder
US7034282B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2004 |
| Grant date | Apr 25, 2006 |
| Priority date | — |
| Expiry date | Jul 7, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/34715
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical rotary encoder for acquiring rotation information regarding a shaft includes a light source located on or in the vicinity of the axis of rotation of the shaft for emitting light rays and a code wheel mounted on the shaft for rotation about the axis of rotation. The code wheel has a plurality of alternating light transmissive and non-light transmissive areas in a circumferential direction. A reflector is spaced a distance from the code wheel for reflecting the light rays emitted from the light source so that they are turned into a parallel beam of light. The parallel beam of light illuminates the light transmissive areas of the code wheel so that light passing through the light transmissive areas is directed toward a peripheral region of the light source. The encoder also includes one or more light-detecting element for detecting the light passing through the light transmissive areas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.