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:
Jul. 27, 2004
Filed:
Apr. 15, 2002
Dale S. Walker, Houston, TX (US);
Duke University, Durham, NC (US);
Abstract
A screen apparatus includes a holographic optical element and a diffuser. The holographic optical element may be constructed using standard techniques known in the field of holography. The holographic optical element may be used to replace a typical Fresnel lens used in projection screen apparatuses. In operation, the holographic optical element receives image light from an image engine or projector and redirects the image light to the diffuser for scattering. The holographic optical element can be designed to substantially collimate, converge, or diverge the image light. The combination of the holographic optical element and the diffuser provides improved illumination uniformity that can be perceived by a viewer as the viewer moves in directions transverse to the screen apparatus. The screen apparatus may be designed to provide improved illumination uniformity to optimized or optimal locations in a viewing region. The screen apparatus may be advantageously employed in display apparatuses.