Radiation interference devices
US4722604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1983 |
| Grant date | Feb 2, 1988 |
| Priority date | — |
| Expiry date | Jan 20, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2009/0211
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An interference device for discriminating between radiation sources of differing coherence length comprises means to divide received radiation from a source into two components. A path difference, defining a coherence length cut-off, is introduced into the path of one component and the components are brought together for interference. The recombined light passes through a reticle with alternate opaque and tranparent bars and an optical band-pass filter to a detector. Interference fringes present in the plane of the reticle are swept across the reticle by the action of the collection optical system of the device which includes a scanning rotating mirror. Two similar devices can be arranged for band-pass coherence length filtering and when used in conjunction with a light soruce whose coherence is modulated the device can be used for signalling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.