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:
Jul. 18, 2006
Filed:
Oct. 06, 2003
Takuro Sugiura, Fukushima-ken, JP;
Takuro Sugiura, Fukushima-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
A front light of the invention has a light guide plate, an intermediate light guide disposed along the side end surface, and a light emitting device disposed on an end surface thereof. The pitch between grooves having a wedge shape in cross section formed on a backside of the light guide on the opposite side of the light guide plate is formed so as to be linearly varied with respect to the distance from an end surface disposed with the light emitting device to the groove. The depth of the groove is formed more deeply as the grooves are positioned more apart from the end surface. In the distribution of the depth of the groove with respect to the distance from the end surface to the groove, there are a first area where the depth of the groove is linearly increased with respect to the distance from the end surface disposed with the light emitting device to the groove, and a second area formed apart from the light emitting device more than the first area in which the increasing rate of the depth of the groove with respect to the distance from the end surface is greater than that in the first area.