Variable density sunglasses comprising light polarizing elements
US4149780A · kind A · utility
36Cited by
3References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 29, 1977 |
| Grant date | Apr 17, 1979 |
| Priority date | — |
| Expiry date | Jun 29, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/12
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Variable density spectacles comprising a pair of superposed iodine stained light polarizing elements, one of such elements being rotatable through an arc of less than 90 degrees to provide changes in the light transmitting functionality of the superposed elements; each of said elements having a light transmittance of from about 42 to 44 percent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.