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:
Jul. 04, 2017
Filed:
Feb. 01, 2016
Panasonic Intellectual Property Management Co., Ltd., Osaka, JP;
Akinori Hiramatsu, Nara, JP;
Shigeru Ido, Osaka, JP;
Daisuke Ueda, Osaka, JP;
Hiroshi Kido, Osaka, JP;
Abstract
The light source unit includes a light source circuit including N (N≧3) pairs of a light source group including one or more solid light emitting elements and a constant current circuit connected in series with the light source group to keep, constant, current flowing through the light source group, a full-wave rectification circuit for performing full-wave rectification on AC voltage, and a control circuit. The first pair is connected to the full-wave rectification circuit. The k-th (2≦k≦N) pair is connected in parallel with the constant current circuit of the (k−1)-th pair so that the light source groups of the k-th and (k−1)-th pairs are in series. The control circuit terminates operations of the constant current circuits of the N pairs or limits currents flowing through the light source groups of the N pairs in response to detection of light or a signal.