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:
Apr. 21, 2009
Filed:
May. 20, 2003
Tomoyoshi Yamashita, Kanagawa, JP;
Masae Ono, Kanagawa, JP;
Tomoyoshi Yamashita, Kanagawa, JP;
Masae Ono, Kanagawa, JP;
Mitsubishi Rayon Co., Ltd., Tokyo, JP;
Abstract
A planar light guide () having a light entrance end face () receiving light from a spot-like primary light source and a light exit face () outputting the entered light, wherein a plurality of lens arrays () are formed, at least a part of the light entrance end face, to extend from the light exit face toward the opposite face substantially in parallel with each other. The lens array () has an asymmetric cross-sectional shape defined by a combination of at least two different curves. When the light guide () is combined with a primary light source disposed oppositely to the light entrance end face () and a light deflecting element disposed oppositely to the-light exit face (), a high quality planar light source having a high uniformity and no variation in luminance is provided even when a relative small number of spot-like light sources are used as the primary light source.