Angle measuring interferometer
US4746216A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 12, 1986 |
| Grant date | May 24, 1988 |
| Priority date | — |
| Expiry date | Jun 12, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/70
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An angle measuring interferometer comprises a source (10) which emits a light beam containing two linear orthogonally polarized components; means, such as a tilted shear plate (16) or a beamsplitter/beam folder assembly (116, 116A) for converting the input beam into two separated, parallel, orthogonally polarized beams; a half-wave retardation plate (29A, 29) located in one of the separated beams for converting the two separated parallel orthogonally polarized beams into two separated parallel beams with the same polarization; means including a polarizing beamsplitter (44), for causing each of the separated parallel beams with the same polarization to be reflected once by each of two plane mirrors (71, 70) to produce two parallel output beams with the same polarization; a half-wave retardation plate (29B, 29) located in one of the separated parallel output beams, for converting the two separated parallel output beams of the same polarization into two separated parallel output beams with orthogonal polarization, with means, such as the tilted shear plate (16) or the beamsplitter/beam folder assembly (116, 116B), converting the two separated parallel orthogonally polarized output bea…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.