Scanning interferometer control systems
US4413908A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1982 |
| Grant date | Nov 8, 1983 |
| Priority date | — |
| Expiry date | Mar 5, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B2290/60
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A scanning interferometer is provided with a substantially monochromatic reference beam having a wavelength outside the spectral region of principal interest. Modulation of the reference beam provides a measure of the scan velocity that is compared with a stablized time reference to provide an error signal used to regulate the scan velocity. Modulation of the reference beam also provides a fringe count. At a predetermined count, the time reference is changed in a pre-arranged manner, providing a pre-established scan acceleration sequence at the end of each scan. The acceleration sequence is selected to insure the direction of the scan is reversed within a quarter wave interval of the fringe count, insuring the fidelity of the fringe-count of the monochromatic reference source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.