Backlight for an image forming device comprising an optical cavity formed by opposing cold and hot mirrors
US11835821B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2022 |
| Grant date | Dec 5, 2023 |
| Priority date | — |
| Expiry date | Sep 26, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/055
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A backlight for an image forming device includes spaced-apart front and back optical reflectors defining an optical cavity therebetween, and at least one light source for emitting light into the optical cavity. The front optical reflector may be disposed between the image forming device and the back optical reflector. For substantially normally incident light and for nonoverlapping first and second wavelength ranges, the front optical reflector may transmit at least 70% of light for each wavelength in the first wavelength range, and may reflect at least 70% of light for each wavelength in the second wavelength range. The back optical reflector may reflect at least 70% of light for each wavelength in the first wavelength range, and may transmit at least 70% of light for each wavelength in the second wavelength range. The emitted light may have at least one wavelength in the first wavelength range and at least one wavelength in the second wavelength range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.