Variable transparency electro-optical device
US5608567A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 11, 1995 |
| Grant date | Mar 4, 1997 |
| Priority date | — |
| Expiry date | Jul 11, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133509
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention relates to a variable transparency electro-optical device comprising: at least one lens formed by an electro-optical cell (4) comprising a first plate (6) and a second plate (8) each provided with a control electrode (14, 16) and a sealing frame (10) interposed between the two plates to form a sealed volume enclosing an electro-optical material (12), voltage generating means (18) connected to said electrodes to apply a variable voltage to said material in order to automatically or manually vary the transmission of the cell (4) as a function of the ambient light. According to the invention the cell (4) comprises at least one element (6) charged with a photochromic substance having an absorption that varies in reversible manner as a function of the intensity of the light impinging on said cell. The invention has particular applications in devices for protecting the eyes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.