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:
Oct. 08, 1996
Filed:
Jun. 02, 1995
Charles B Mattas, Glenview, IL (US);
Robert A Erhardt, Torrance, CA (US);
Philips Electronics North America Corp., New York, NY (US);
Abstract
An electronic ballast for powering at least two rapid start, parallel connected fluorescent lamps. Associated with each lamp is a serially connected choke and capacitor combination. A train of pulses of alternating polarity having a fundamental frequency, which is generated by an inverter, is applied to each serially connected combination. Each combination is characterized by a resonant frequency which is other than an odd harmonic of and at least two times and preferably .sqroot. 5 times greater than the fundamental frequency. Reduction in filament heating, following lamp ignition, is provided through the addition of voltages applied to each filament which are substantially out of phase with each other.