Enhanced light diffusing sheet
US7914192B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 27, 2007 |
| Grant date | Mar 29, 2011 |
| Priority date | — |
| Expiry date | Jan 19, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/0065
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light transmitting diffusing sheet can be used in backlighting systems for liquid crystal displays (LCDs). Such displays are typically used in televisions, computer monitors, laptop computers and handheld devices such as mobile phones. Embodiments of the light diffusing sheets are suitable for use with both cold-cathode fluorescent (CCFL) and light emitting diode based backlighting systems. Desired light transmitting properties in the light transmitting diffusing sheet have been achieved by modifying both the volume and surface features of the sheet. Embodiments of this invention when used as part of the backlighting assembly for a LCD system results in improved brightness and controlled viewing angles. In one embodiment, substantially asymmetric particles in the volume of the sheet are combined with a ridged structure on one surface of the sheet. The use of the sheet removes the need for separate prismatic films and diffusing sheets, while also optimizing the light transmitting properties of these two elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.