Fringe pattern discriminator for grazing incidence interferometer
US6757067B2 · kind B2 · utility
2Cited by
5References
23Claims
0Family size
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Key dates
| Filing date | Aug 6, 2002 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Aug 6, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B9/02084
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Flatness and thickness variation information concerning transmissive plane-parallel test plates is obtained from a grazing incidence interferometer modified to distinguish between superimposed interference patterns containing both types of information. The grazing angle of the interferometer is varied, and unique modulation frequencies of local fringe intensities within the superimposed interference patterns are identified. The local fringe intensities attributable to the different interference patterns are distinguished by their respective modulation frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.