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:
Jan. 10, 2012
Filed:
Feb. 05, 2009
Ka Hong Loo, Hong Kong, HK;
Wai Keung Lun, Hong Kong, HK;
Yuk Ming Lai, Hong Kong, HK;
Siew Chong Tan, Hong Kong, HK;
Chi Kong Michael Tse, Hong Kong, HK;
Ka Hong Loo, Hong Kong, HK;
Wai Keung Lun, Hong Kong, HK;
Yuk Ming Lai, Hong Kong, HK;
Siew Chong Tan, Hong Kong, HK;
Chi Kong Michael Tse, Hong Kong, HK;
The Hong Kong Polytechnic University, Kowloon, HK;
Abstract
A driving method for improving luminous efficacy of a light emitting diode (LED), the method comprising: periodically switching a DC current supplied to the LED between a high current level land a low current level l, the low current level lbeing fixed at zero or raised above zero to produce a DC offset; and maintaining an average current at a first valueby adjusting the duty cycle acting on the high current level land any one from the grouping consisting of: adjusting the high current level land adjusting the low current level l, and adjusting the high current level lor adjusting the low current level l.