Screen, a fresnel lens sheet used for the screen, and an image display apparatus using the screen
US7440186B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 18, 2005 |
| Grant date | Oct 21, 2008 |
| Priority date | — |
| Expiry date | Apr 27, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/625
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a technology suitable for shortening a depth of a image display apparatus while obtaining a picture of high quality. According to the invention, a total reflection prism portion is provided on a side of a Fresnel lens sheet toward a picture source. The total reflection prism portion reflects an incident light to a direction toward an optic axial center of the Fresnel lens sheet to have the same outgoing. On the other hand, a first refractive prism portion, by which light of a predetermined incident angle or less is refracted to outgo to a direction along an optical axis of the Fresnel lens sheet, and a second refractive prism portion, by which light reflected to the direction toward the optic axial center of the Fresnel lens sheet is changed to the direction along the optical axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.