Photoelectric encoder
US7570433B2 · kind B2 · utility
2Cited by
16References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 18, 2005 |
| Grant date | Aug 4, 2009 |
| Priority date | — |
| Expiry date | Mar 18, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/36
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A photoelectric encoder has a telecentric optical system in which a first lens and an aperture located at a focal position of the first lens are interposed between a main scale and a photoreceptor. At least a second lens is interposed between the aperture and the photoreceptor with a focus of the second lens on the aperture, thereby constituting a bilateral telecentric optical system. This makes it possible to improve the signal detection efficiency and increase the assembly tolerance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.