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. 22, 1989
Filed:
Apr. 25, 1988
William M Keeffe, Rockport, MA (US);
Zeya Krasko, Beverly, MA (US);
Robert Karlotski, Weare, NH (US);
James C Morris, Wakefield, MA (US);
GTE Products Corporation, Danvers, MA (US);
Abstract
An improved metal-halide arc discharge lamp includes an arc tube having a substantially cylindrical body surrounded laterally by a substantially cylindrical heat-conserving sleeve within an evacuated outer envelope. The ratio of the outer radius of the arc tube divided by the inner radius of the sleeve falls within an optimum range of approximately 0.54 to approximately 0.68, and preferably within a range of approximately 0.60 to approximately 0.63. A lamp constructed in accordance with the invention exhibits improved luminous efficacy and color rendering in comparison to prior art counterparts. The improved performance is believed to be attributable to the more nearly isothermal operation of the arc tube for a given wall loading.