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. 01, 2013
Filed:
Mar. 23, 2010
Junji Matsuda, Tokyo, JP;
Mitsunari Yoshida, Tokyo, JP;
Junji Matsuda, Tokyo, JP;
Mitsunari Yoshida, Tokyo, JP;
Stanley Electric Co., Ltd., Tokyo, JP;
Abstract
A long-life hot cathode fluorescent lamp can include a pair of parallel lead wires that can be arranged at each end of a tube. A coiled filament can be connected at its opposite end portions to the lead wires. The coiled filament can have two long pitched regions in which a coil pitch is longer than regions outside of the long pitched regions. Emitter can be located in a region defined between the two long pitched regions. Shape characteristics and intensive current flow obtained by the presence of the long pitched regions can form the origins of discharge near the boundaries between long and short pitched regions. Accordingly, stable discharge can be achieved with the origins of discharge located at ends of the emitter. As a result, the hot cathode fluorescent lamp is allowed to have a long life and stable light emission characteristics.