Process and apparatus for performing differential refractive index measurements using interference of modulated light beams passing through reference and test samples
US5483344A · kind A · utility
6Cited by
8References
24Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Aug 19, 1994 |
| Grant date | Jan 9, 1996 |
| Priority date | — |
| Expiry date | Aug 19, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N30/74
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to the measurement of the difference between refractive indexes of two media, traversed by a light beam the beams produce an interference figure consisting of fringes having a displacement which is measured. According to the invention, the displacement of the fringes of the interference figure is detected with a photosensitive device and a phase modulation is performed on at least one of the beams and the modulation is controlled in order to obtain a movement of the fringes of the interference figure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.