Ultraviolet radiation and blue light blocking polarizing lens
US5177509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 1989 |
| Grant date | Jan 5, 1993 |
| Priority date | — |
| Expiry date | Oct 13, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/16
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A lens (10) that substantially blocks horizontally polarized light and selectively blocks wavelengths between 300 and 549 nanometers. The selective blocking is controlled by a sharp cut-on filter (14) selected to cut-on at either 450, 500, 515, 530, or 550 nanometers. The specific blocking and cut-on point selected is dependent upon the ultimate usage/environment of the lens (10). If a 450 cut-on filter is selected, wavelengths between 300 and 449 nanometers are blocked before a cut-on occurs at 450 nanometers; similarly, a 550 cut-on filter blocks wavelengths between 300 and 549 nanometers before a cut-on occurs at 550 nanometers. The lens (10) also allows 30 to 40 percent of wavelengths over 625 nanometers to be transmitted. The filter (14) in combination with the polarizer (16) blocks harmful Ultraviolet radiation and blue light. While a beneficial and calming effect is achieved by wearing only blue-blocking lenses, the addition of the polarizer (16) substantially enhances the calming effect and the improvement of vision without visual discomfort.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.