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. 09, 2017
Filed:
Dec. 18, 2009
Applicant:
Timo Toivola, Turku, FI;
Inventor:
Timo Toivola, Turku, FI;
Assignee:
Nokia Technologies Oy, Espoo, FI;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H05B 37/02 (2006.01); H05B 33/08 (2006.01);
U.S. Cl.
CPC ...
H05B 33/0821 (2013.01);
Abstract
A method and an apparatus are provided. The apparatus comprises a power source node; a light-emitting diode; a full-wave rectifier configured to produce unipolar half-waves from an alternative current mains supply connected to the power source node; and a voltage controlled switch configured to drive the light-emitting diode with pulses, each pulse derived from a half-wave, the width of the pulses being inversely proportional to mains supply voltage.