Displacement detecting device
US8363230B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 20, 2011 |
| Grant date | Jan 29, 2013 |
| Priority date | — |
| Expiry date | Jul 26, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/0608
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A displacement detecting device comprises: a light source, a first beam splitter adapted to split the light emitted from the light source into a first beam and a second beam, a reflecting member adapted to reflect the first beam, an objective lens adapted to condense the second beam on a surface-to-be-measured, a first light receiving section adapted to receive interference light of the reflected first beam and the reflected second beam, a relative position information output section adapted to output relative position information in height direction of the surface-to-be-measured, a second beam splitter adapted to extract a part of the reflected second beam, an astigmatism generator adapted to generate astigmatism in the extracted second beam, a second light receiving section adapted to receive the second beam having astigmatism, and an absolute position information output section adapted to generate absolute position information in height direction of the surface-to-be-measured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.