Interferometer apparatus for both low and high coherence measurement and method thereof
US6992779B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 29, 2003 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Aug 5, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B9/0209
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A Fizeau interferometer apparatus is used for both low and high interference measurement. When irradiating a reference surface and a sample with a low coherent luminous flux, a path-matching passage divides the low coherent luminous flux into first and second paths, while the optical path length difference between the respective luminous fluxes passed through the two paths equals twice the optical distance between the reference surface and the sample. When irradiating the reference surface and the sample with a high coherent luminous flux, the luminous flux is made incident on the sample side of the path-matching passage at a position coaxial with the low coherent luminous flux.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.