Fixed-point detector and displacement-measuring apparatus
US7808649B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 2008 |
| Grant date | Oct 5, 2010 |
| Priority date | — |
| Expiry date | Jun 24, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/38
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A fixed-point detector is provided. The fixed-point detector includes a plurality of fixed-point detecting patterns, a fixed-point detecting light source, and a plurality of photoelectric conversion elements. The plurality of fixed-point detecting patterns each have a pair of diffraction gratings for diffracting incident light in different directions. The fixed-point detecting light source irradiates the pair of diffraction gratings with light while moving in the measurement-axis direction with respect to the plurality of fixed-point detecting patterns. The plurality of photoelectric conversion elements move together with the fixed-point detecting light source, while receiving light beams diffracted by the respective diffraction gratings of the plurality of fixed-point detecting patterns and converting the diffracted light beams into electric signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.