Patent · US Expired

Projection screen and projection system comprising the same

US7057813B2 · kind B2 · utility

4Cited by
4References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 21, 2004
Grant dateJun 6, 2006
Priority date
Expiry dateNov 25, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B21/625
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The present invention provides a projection screen capable of sharply displaying an image even under bright environmental light, of improving brightness distribution and viewing angle, and of providing high image visibility, and a projection system including such a projection screen. The projection screen includes: a polarized-light selective reflection layer that selectively reflects a specific polarized-light component; a substrate that supports the polarized-light selective reflection layer and a circular Fresnel lens provided on the observation side of the polarized-light selective reflection layer. The circular Fresnel lens controls the optical axis of right-handed circularly polarized light projected on the projection screen so that the light enters the polarized-light selective reflection layer nearly vertically to it regardless of the point and angle at which the light is incident on this layer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.