Tunable variable bandpass optical filter
US6700690B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2001 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Jan 22, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2003/1243
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A variable bandwidth tunable optical filters comprised of two transparent optical substrates, upon each of which is deposited a linearly variable multilayer interference filter coating which varies in total thickness from end to end in a wedged fashion. This wedge imparts a corresponding variation of the center wavelength of the filter bandpass with respect to the linear position of the coated filter substrates. The variable bandpass tunable filter can be adjusted to a specific center wavelength by moving the filter pair together linearly through the incident beam. The bandwidth of the filter pair is maximized when the two filters are spectrally aligned, and is determined by the bandwidth of the individual filters. The variable bandwidth of the tunable filter can be adjusted by introducing a relative linear offset between the linearly variable filter pair.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.