Fixed wavelength absolute distance interferometer
US8179534B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 11, 2010 |
| Grant date | May 15, 2012 |
| Priority date | — |
| Expiry date | Dec 4, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/60
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A fixed wavelength absolute distance interferometer including a first interferometer comprising a first light source transmitting a first light beam having a wavelength W toward a measurement target, a wavefront radius detector configured to provide a first measurement responsive to the wavefront radius at the wavefront radius detector, and a first path length calculating portion calculating a coarse resolution absolute path length measurement R; and a second interferometer comprising a beam transmitting device transmitting a second-interferometer light beam having a wavelength Λ, a beam splitting/combining device separating the second-interferometer light beam into reference and measurement beams and combining the returning reference and measurement beams into a combined beam, a second-interferometer detector configured to receive the combined beam and provide signals of a phase φ of the combined beam, and a second path length calculating portion configured to determine a medium resolution absolute path length measurement ZM.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.