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:
Jun. 12, 2007
Filed:
Jun. 30, 2005
Yu Huang, Los Angeles, CA (US);
Yu Huang, Los Angeles, CA (US);
Luminoz, Inc., Tokyo, JP;
Abstract
An off-axis Fresnel lens is disclosed that, when combined with a rear projection screen (comprising, e.g., a lenticular lens, a diffuser, or both), enables construction of rear-projection-type screen devices (e.g., projection television systems) that are thinner and have improved contrast and resolution when compared with conventional projection screen devices. The off-axis Fresnel lens comprises a plurality of concentric, outwardly-extending, total internal reflection-type prism facets. Each facet, in turn, comprises top and bottom sides, one or both of which may be flat or outwardly convex. Embodiments of the invention may also include concentric opaque sections that are disposed between successive prisms, between the prism base and the output surface of the Fresnel lens, and/or between the output surface of the Fresnel lens and the input surface of the projection screen in order to improve contrast. Contrast may also be enhanced by laminating the Fresnel lens to the projection screen.