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:
Aug. 05, 2008
Filed:
Apr. 04, 2005
Masahiro Goto, Shinjuku-Ku, JP;
Mitsuru Iida, Shinjuku-Ku, JP;
Wataru Tokuhara, Shinjuku-Ku, JP;
Dai Nippon Printing Co., Ltd., Shinjuku-Ku, JP;
Abstract
A diffusing sheet, a surface light source unit, and a transmission type display that can attain uniform illumination so that the brightness of light on the display screen appears uniform regardless of the position from which the display screen is observed. The diffusing sheet includes, on its light-emerging side surface, a diffusion lens array having a plurality of unit lenses, each unit lens being in a shape equivalent to a part of an elliptic cylinder having an elliptical cross section. The surface light source unit includes the diffusing sheet and a convergent sheetthat has a plurality of unit lenseshaving almost trapezoidal cross sections, formed on one surface thereof. It is possible to attain uniform illumination by diffusing light from cathode ray tubes in the surface light source unit, and, at the same time, to converge the light serving as backlight to enhance optical efficiency.