Illumination system using optical feedback
US6507419B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2000 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Mar 23, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/13342
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed is an illumination system using optical feedback to maintain a predetermined illumination output. The illumination system employs an electrically controllable optical filter for filtering light incident thereon. The illumination system also includes a light detector for detecting at least a portion of the light filtered by the electrically controllable optical filter. The light detector is in data communication with the electrically controllable optical filter. Some or all light filtered by the electrically controllable optical filter is detected by the light detector, which, in turn generates a corresponding signal that is compared to at least one predetermined value. If the signal generated by the light detector differs when compared to the at least one predetermined value, one or more filtering characteristics of electrically controllable optical filter are varied which, in turn, varies the amount of light filtered by the electrically controllable optical filter. The filtering characteristics of the electrically controllable optical filter continue to be varied until the signal generated by the light etector substantially matches the at least one predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.