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:
Nov. 15, 2005
Filed:
Jan. 16, 2002
Horst Greiner, Aachen, DE;
Horst Greiner, Aachen, DE;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A lighting device is described which comprises a light emission surface () and a plurality of substantially point-shaped light sources () such as, for example, LEDs, and which is suitable in particular for backlighting liquid crystal displays such as LCD picture screens, or for use as a planar light radiator. The lighting device is characterized in particular in that an optical waveguide plate () is provided with a plurality of cavities () for the light sources (), which cavities are covered with a first reflecting layer () on their upper sides () facing the light emission surface (), while the coupling of the light into the optical waveguide plate takes place through side walls () of the cavities. A very homogeneous distribution of the luminous intensity on the light emission surface is achieved thereby.