Polarization insensitive tunable optical filters
US6781757B2 · kind B2 · utility
9Cited by
27References
18Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 19, 2002 |
| Grant date | Aug 24, 2004 |
| Priority date | — |
| Expiry date | Apr 19, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A polarization insensitive tunable optical filter system combines an interference filter or the like with a quarter wave plate and a retro-reflector. The retro-reflector is situated and aligned to intercept light reflected from the filter, and the quarter wave plate is disposed between the filter and the retro-reflector. Hence, the pass signal reflected off the filter a first time passes through the quarter wave plate a first time, reflects off of the retro-reflector, passes through the quarter wave plate a second time, and reflects off of the filter a second time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.