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:
Sep. 17, 2013
Filed:
Oct. 15, 2009
Hans-peter Loebl, Monschau-Imgenbroich, DE;
Stefan P. Grabowski, Neuss, DE;
Hans-Peter Loebl, Monschau-Imgenbroich, DE;
Stefan P. Grabowski, Neuss, DE;
Koninklijke Philips N.V., Eindhoven, NL;
Abstract
A light emitting diode driving apparatus () comprises an arrangement () for supplying a signal to light emitting diodes (). The light emitting diodes () comprise different internal impedances () for producing different light outputs in response to a parameter of the signal having different values. As a result, the light emitting diodes () can be driven relatively independently from each other. Each light output may have an intensity and/or a color. Different light outputs may have different intensities for dimming purposes and/or different colors for color tuning purposes. The parameter may comprise a frequency parameter and/or a timing parameter. The light emitting diodes () may form parts of a serial branch, for example when being stacked organic light emitting diodes, or may form part of parallel branches. The internal impedances () may comprise capacities () and resistivities ().