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:
May. 13, 2003
Filed:
Mar. 16, 2001
Masaya Adachi, Hitachi, JP;
Ikuo Hiyama, Hitachi, JP;
Makoto Tsumura, Hitachi, JP;
Shusuke Endo, Mobara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A lighting unit is provided which comprises: a plurality of linear light sources arranged in parallel; light-guiding plates arranged along said light sources; light diffusion means arranged at the top of said light sources and light-guiding plates; and reflection means arranged at the bottom of the light sources; wherein said lighting unit is characterized in that the surface of each light-guiding plate is flat, in that the reverse side of the light-guiding plate includes an inclined face of a curvilinear shape that thins down as the inclined face is more distanced from the light source, and in that when a position relatively near the light source and a position relatively far from the light source, on the reverse side of the light-guiding plate, are inclined by &thgr;n1 and &thgr;f1, respectively, the relationship of &thgr;n1 ≧&thgr;f1 is satisfied and the angle-of-inclination of the thinnest portion on the reverse side of the light-guiding plate is 0 degrees. With this arrangement, supply of a thin lighting unit that is high in luminance and in the in-plane uniformity of luminance can be obtained.