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. 23, 2003
Filed:
Oct. 08, 2001
Randall D. Blanchard, San Diego, CA (US);
Other;
Abstract
An apparatus for controlling the brightness of an electrodeless fluorescent lamp excited by power supplied to a coil disposed in closed proximity to said lamp. The apparatus includes a dimming control unit responsive to a brightness setting for the lamp that provides a PWM signal indicative of the brightness setting. An oscillator is disposed for producing a first lamp drive voltage having a first frequency selected in response to a first state of the PWM signal and a second lamp drive voltage having a second frequency selected in response to a second state of the PWM signal. Accordingly, the first drive voltage turns on the lamp by transferring maximum power to the lamp and the second drive voltage turns off the lamp by transferring minimum power to the lamp.