Optical filter assembly with selectable bandwidth and rejection
US7655898B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 5, 2007 |
| Grant date | Feb 2, 2010 |
| Priority date | — |
| Expiry date | Sep 5, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2003/1213
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical filter assembly having selectable bandwidth is presented. The optical filter assembly includes a first optical filter, a first optical retarder with optical retardance R1, a second optical retarder with optical retardance R2, a polarization switch positioned between the first and second retarders which causes their retardances to substantially add in a first switch setting and to substantially subtract in a second switch setting, and an exit polarizer. A multispectral imaging system using tunable optical filters having selectable bandwidth is presented. A method of filtering light is also presented. The method includes providing a first optical filter, providing a dynamic bandwidth stage including a polarization switch, selecting a first setting of the polarization switch, and producing a first filter action for light passing through the first filter and the dynamic bandwidth stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.