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:
Nov. 30, 1993
Filed:
Mar. 27, 1991
Masami Takagi, Yokohama, JP;
Hidehiko Noguchi, Imabari, JP;
Toshiba Lighting & Technology Corporation, Tokyo, JP;
Abstract
A low pressure gas discharge lamp comprises an elongated tube filled with a discharge gas. An inner electrode is disposed in a first end portion of the tube and an outer electrode is formed on an outer surface of the tube. The outer electrode has a belt shaped portion formed on the outer surface of the tube along an axial direction of the tube between the first end portion and a second end portion of the tube and a ring shaped portion formed on the outer surface of the tube around the second end portion of the tube. The ring shaped portion is connected to the belt shaped portion. The discharge is generated between the inner electrode and the outer electrode. The ring shaped portion of the outer electrode prevents the discharge from shifting from a central axis of the tube, and thus makes the lamp have an even brightness distribution along the axis of the tube.