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. 26, 2000
Filed:
Sep. 11, 1998
Koji Kawada, Hadano, JP;
Yoji Oki, Yokohama, JP;
Masaru Suzuki, Yokohama, JP;
Yoshiteru Watanabe, Sagamihara, JP;
IBM Corporation, Armonk, NY (US);
Stanley Electric Co., Ltd., Tokyo, JP;
Abstract
The invention is intended to reduce the weight of the entire unit, make it compact and prevent the emitted light from being in dark and bright stripes in a light guide unit for a back light of a liquid crystal display device. Further, this invention allows a prism sheet having a larger apex angle to be used. To this end, the light guide unit comprises a plurality of light guide films laminated on the light guide member. The sloped surface which is opposite to the incident surface of the light guide unit is formed with grooves each having an inclination of an angle related to Brewster angle. A prism sheet is further disposed with the side having apexes oriented to the light guide unit to deflect the light emitted from the light guide unit.