Light guides suitable for illuminated displays
US6893135B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2001 |
| Grant date | May 17, 2005 |
| Priority date | — |
| Expiry date | Mar 28, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0071
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light guide (1) comprises a housing (3) defining a light-guiding optical cavity having first and second opposed major faces (5, 6), and a light source (11) arranged to direct light into the cavity from one end, to be guided between the major faces. The first major face (5) comprises a window through which light can be emitted from the optical cavity to be used, for example, for illuminating a graphic display. To improve the light distribution across that first major face (5), the second major face (6) comprises a sheet material (23) having a specularly-reflecting surface (24) that faces into the optical cavity and has diffusely-reflecting light-extraction elements (27) applied thereto in a predetermined configuration for causing light to be emitted from the optical cavity through the said window.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.