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:
Mar. 03, 1992
Filed:
Dec. 26, 1989
Applicant:
Inventors:
Tsutomu Watanabe, Yokosuka, JP;
Takumi Suwa, Fujisawa, JP;
Assignee:
Toshiba Lighting & Technology Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01K / ;
U.S. Cl.
CPC ...
313 25 ; 313113 ; 313578 ; 313635 ;
Abstract
In a double bulb type halogen lamp, a sealed space between the inner surface of an outer bulb and the outer surface of the inner bulb in which a coiled filament is disposed is filled with a weak oxidation gas to avoid deoxidation of the optical interference film composed of metal oxide substances exposed to the sealed space.