Light guide plate, surface light source device and liquid crystal display
US6485157B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 26, 2001 |
| Grant date | Nov 26, 2002 |
| Priority date | — |
| Expiry date | Mar 26, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S385/901
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A surface light source device and LCD employs a light guide plate which is capable of a three-dimensional emission direction controlling and avoids fine unevenness in brightness from appearing. Light guide plate 34 has a back face 34 provided with a great number of micro-reflectors 90 each of which has a guiding portion and a conversion output portion including a valley getting narrower and shallower as being distant from the guiding portion. The conversion output portion reflects input light P twice at inner slopes to produce inner output light Q. Inner output light Q is inner-incident to a slope of projection raw PR. While some of the inner incident light becomes directly escaping light, some other of the inner incident light fails to escape directly, reaching emission face 33 after travelling further along various light paths. Indirectly escaping light is emitted at second or later chances of emission. Directly escaping light and indirectly escaping light overlap, thereby preventing fine unevenness in brightness from appearing. It is advantageous to dispose reflector RF for increasing indirectly escaping light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.