Rear projection type image display unit
US6771419B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2001 |
| Grant date | Aug 3, 2004 |
| Priority date | — |
| Expiry date | Jun 28, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Color lights from image projecting sections (207) that enlarge and project images of red, green and blue, respectively, are made incident on a transparent screen at different angles of incidence, so that image synthesis is carried out. The color lights projected are converted into telecentric light by a Fresnel lens (211), and after principal rays of the respective color lights are converted into substantially parallel rays by a color shading eliminating means (219) provided with lenticular lenses on both sides thereof, the rays are incident on a light diffusing means (224). The light diffusing means (224) is formed with a transparent substrate sheet and a plurality of transparent micro beads made to adhere onto a light-incident surface of the substrate sheet with an opaque adhesive. Image light passes through light transmitting portions between the substrate sheet and the micro beads to be diffused. This configuration enables to provide a rear-projection image display whose display images are hardly affected by external light, which has an increased angle of visibility, and which undergoes less color shading, without a decrease in light utilization efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.