Extending the range of spectrally controlled interferometry by superposition of multiple spectral modulations
US11385044B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 15, 2020 |
| Grant date | Jul 12, 2022 |
| Priority date | — |
| Expiry date | Aug 4, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B9/02057
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The range of measurement in spectrally controlled interferometry (SCI) is extended by superimposing multiple modulations on the low-coherence light used for the measurement. Optimally, a spectrally controllable light source modulated sinusoidally with low spectral frequency is combined with a delay line, such as provided by a Michelson interferometer. The resulting light is injected into a Fizeau interferometer to generate localized fringes at a distance corresponding to the effect of the spectrally modulated source combined with the optical path difference produced by the delay line. The combination provides a convenient way to practice SCI with all its advantages and with a range that can be extended to the degree required for any practically foreseeable application. Alternatively, a single source capable of multiple modulations can be used instead of a separate second modulator component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.