Linear-carrier phase-mask interferometer
US7777895B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 2007 |
| Grant date | Aug 17, 2010 |
| Priority date | — |
| Expiry date | Aug 31, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A phase-difference sensor measures the spatially resolved difference in phase between orthogonally polarized reference and test wavefronts. The sensor is constructed as a linear-carrier phase-mask aligned to and imaged on a linear-carrier detector array. Each adjacent element of the phase-mask measures a predetermined relative phase shift between the orthogonally polarized reference and test beams. Thus, multiple phase-shifted interferograms can be synthesized at the same time by combining pixels with identical phase-shifts. The multiple phase-shifted interferograms can be combined to calculate standard parameters such as modulation index or average phase step. Any configuration of interferometer that produces orthogonally polarized reference and object beams may be combined with the phase-difference sensor of the invention to provide single-shot, simultaneous phase-shifting measurements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.