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:
Aug. 02, 1983
Filed:
Nov. 19, 1980
Matsushita Electronics Corporation, Osaka, JP;
Abstract
Each of the electrodes at the ends of an arc tube filled with a buffer gas, metal and sodium comprises an electrode core, an electrode coil wound around the core, an electron-emitting means disposed in the annular space between the electrode core and electrode coil and a shielding means disposed in said annular space in such a way that the electron-emitting means is shielded from exposure to the discharge space in the arc tube. The ratio h/d is determined such that 0.8.ltoreq.h/d.ltoreq.5.4, where h is the length in mm of the portion of the electrode core extended beyond the inner end of the shielding means or the innermost coil of the electrode coil; and d is the diameter in mm of the electrode core. The arc spots can be held to remain on the end faces of the electrode cores during lamp operation so that variations in electrical and optical characteristics can be almost eliminated.