Dual laser high precision interferometer
US7292347B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 2005 |
| Grant date | Nov 6, 2007 |
| Priority date | — |
| Expiry date | Jun 24, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An absolute distance measuring device based on laser interferometry may combine coarse, intermediate, and highest resolution measurement techniques to find the absolute distance to a sample surface with high resolution. The device may provide at least two laser wavelengths simultaneously, to allow reduction or elimination of certain common-mode error components, including dynamic error components. The device may scan at least one of the laser wavelengths over a relatively narrow range and may use quadrature detectors to provide enough signal data to allow certain self-corrections to be performed on the resulting scanned signals and measurements. A novel tunable laser and/or quadrature detector may provide advantages in combination with the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.