Optical filters
US4946245A · kind A · utility
120Cited by
9References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 17, 1989 |
| Grant date | Aug 7, 1990 |
| Priority date | — |
| Expiry date | May 17, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/055
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical filter includes a volume diffraction grating provided within a waveguide. The grating has a thickness T sufficient such that when an optical beam R is incident on the grating from outside the waveguide, wavelengths at or near the Bragg wavelength for the grating are diffracted and coupled into the waveguide, all but the first order interferences being substantially eliminated, while wavelengths away from the Bragg wavelength pass through the waveguide substantially undiffracted. The grating pitch L may be varied to permit tuning of the filter response.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.