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:
Mar. 20, 1990
Filed:
Aug. 23, 1988
Akira Kobayashi, Mobara, JP;
Tooru Sano, Mobara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A light source device has a transparent plate having a smoothened front surface and a roughened rear surface. A light source is disposed adjacent to an end face of the transparent plate. The roughened rear surface has a portion which is inclined and curved and disposed adjacent to the end of the transparent plate remote from the light source. A reflecting plate is disposed adjacent to and extends along the roughened rear surface of the transparent plate. The provision of the inclined and curved surface portion assures that the luminance of the light on the smoothened front surface of the transparent plate is substantially uniform over the entire surface area. The inclined and curved surface portion is represented by the following equation,