Interferometer with continuously varying path length measured in wavelengths to the reference mirror
US9464882B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 4, 2013 |
| Grant date | Oct 11, 2016 |
| Priority date | — |
| Expiry date | Apr 4, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B9/02067
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An interferometer in which the path length of the reference beam, measured in wavelengths, is continuously changing in sinusoidal fashion and the interference signal created by combining the measurement beam and the reference beam is processed in real time to obtain the physical distance along the measurement beam between the measured surface and a spatial reference frame such as the beam splitter. The processing involves analyzing the Fourier series of the intensity signal at one or more optical detectors in real time and using the time-domain multi-frequency harmonic signals to extract the phase information independently at each pixel position of one or more optical detectors and converting the phase information to distance information.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.