The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 18, 2007
Filed:
Mar. 18, 2004
Futoshi Osawa, Shinjuku-Ku, JP;
Makoto Honda, Shinjuku-Ku, JP;
Futoshi Osawa, Shinjuku-Ku, JP;
Makoto Honda, Shinjuku-Ku, JP;
Dai Nippon Printing Co., Ltd., Tokyo, JP;
Abstract
A transmission screen is capable of preventing the reduction of contrast in images due to external light such as emitted by internal lighting fixtures. The transmission screen includes a Fresnel lens sheet having a front surface facing the viewer and provided with Fresnel lens elements, and a shading sheetplaced contiguously with the front surface of the Fresnel lens sheet. The shading sheetis provided with shading elementsfor absorbing external light fallen on the front surface of the shading sheetand reflected in a total reflection mode by the back surface of the Fresnel lens sheet facing a projection light source toward the viewer. Preferably, the shading elementstransmit at least external light fallen on the shading sheet at an incident angle θ satisfying a condition expressed by: θ<24+0.018×F, where θ is incident angle of external light that falls on the shading sheet, and F is the focal length of the Fresnel lens elements in millimeter.