Optical filter and spectrometer
US9625628B2 · kind B2 · utility
12Cited by
10References
34Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2015 |
| Grant date | Apr 18, 2017 |
| Priority date | — |
| Expiry date | Jan 29, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2003/2813
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An optical filter is disclosed including two laterally variable bandpass filters stacked at a fixed distance from each other, so that the upstream filter functions as a spatial filter for the downstream filter. This happens because an oblique beam transmitted by the upstream filter is displaced laterally when impinging on the downstream filter. The lateral displacement causes a suppression of the oblique beam when transmission passbands at impinging locations of the oblique beam onto the upstream and downstream filters do not overlap.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.