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:
Oct. 11, 2005
Filed:
Feb. 10, 2003
Mituso Ohizumi, Fukushima-ken, JP;
Takuro Sugiura, Fukushima-ken, JP;
Mituso Ohizumi, Fukushima-ken, JP;
Takuro Sugiura, Fukushima-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
A surface-emitting device includes a light guide panel, a light guide placed along one end face of the light guide panel, and light sources placed at ends of the light guide. A side face of the light guide facing the end face of the light guide panel serves as an emergent surface for applying light from the light sources to the light guide panel, and a side face remote from the emergent surface serves as a reflecting surface on which concave grooves for reflecting light propagating inside the light guide are periodically formed at a predetermined pitch. The depth of the concave grooves increases toward the center of the light guide, and the angle formed between two inclined faces that constitute each groove is within the range of 105° to 115°.