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. 06, 2016
Filed:
Nov. 15, 2012
Panasonic Corporation, Osaka, JP;
Yohei Hayashi, Osaka, JP;
Hirofumi Konishi, Osaka, JP;
Masanori Mishima, Kyoto, JP;
Masanao Okawa, Nara, JP;
Abstract
A light-emitting-element lighting circuit for dimming a light emitting element by a PWM dimming signal of a duty ratio corresponding to an input dimming signal is provided. The lighting circuit includes a PWM dimming signal generating unit which generates the PWM dimming signal by performing a summation of AC wave signals including a fundamental wave and harmonics of different frequencies that are integer multiples of a fundamental frequency of the fundamental wave. The fundamental frequency is equal to or higher than a frequency, at which a sound pressure level is at maximum, in an audible frequency range in a correlation spectrum between the sound pressure level generated from the light emitting element and a frequency of an AC wave signal inputted to the light emitting element.