Optical filter comprising a variable transmittance layer
US9921421B2 · kind B2 · utility
16Cited by
8References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 18, 2017 |
| Grant date | Mar 20, 2018 |
| Priority date | — |
| Expiry date | Jan 18, 2037 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49826
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A optical filter comprising a variable transmittance layer having a first spectrum in a dark state, and a second spectrum in a faded state; and a color balancing layer having a third spectrum; each of the first, second and third spectra comprising a visible portion; the first and third spectra combining to provide a dark state spectrum approximating a dark state target color; and the second and third spectra combining to provide a fades state spectrum approximating a faded state target color. The optical filter may further comprise a light attenuating layer. The optical filter may further comprise part of a laminated glass.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.