Dynamic optical filter having a spatial light modulator
US7019883B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 3, 2002 |
| Grant date | Mar 28, 2006 |
| Priority date | — |
| Expiry date | Oct 21, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2011/0026
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An dynamic optical filter 10 is provided to selectively attenuate or filter a wavelength band(s) of light (i.e., optical channel(s)) or a group(s) of wavelength bands of an optical WDM input signal 12. The optical filter is controllable or programmable to selectively provide a desired filter function. The optical filter 10 includes a spatial light modulator 36, which comprises an array of micromirrors 52 that effectively forms a two-dimensional diffraction grating mounted in a retro-reflecting configuration. Each optical channel 14 is dispersed separately or overlappingly onto the array of micro-mirrors 52 along a spectral axis or direction 55 such that each optical channel or group of optical channels are spread over a plurality of micromirrors to effectively pixelate each of the optical channels or input signal. Each channel 14 or group of channels may be selectively attenuated by flipping or tilting a selected number of micromirrors to thereby deflect a portion of the incident radiation away from the return optical path. The micro-mirrors operate in a digital manner by flipping between a first and second position in response to a control signal 56 provided by a controller 58 in …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.