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:
May. 26, 1992
Filed:
Dec. 31, 1990
Brian J Thomas, Phoenix, NY (US);
Daniel C Briggs, Camillus, NY (US);
Michael Avdenko, Skaneateles Falls, NY (US);
Welch Allyn, Inc., Skaneateles Falls, NY (US);
Abstract
A low-wattage metal-halide discharge lamp has a quartz tube of the double-ended type that forms a bulb or envelope, a pair of electrodes, e.g., an anode and a cathode, which penetrate into an arc chamber inside the envelope, and a suitable amount of mercury plus one or more metal halide salts. The electrodes are each formed of a refractory metal, i.e., tungsten wire, extending through the respective necks into the arc chamber. Heat dissipation through the neck is controlled by constructing the quartz shanks to that they have shank segments of a desired surface area that extend from the necks a distance equal to the length of the arc chamber. A shank segment loading factor defined as the rated power divided by the shank segment surface areas, and should be in a target range of 12 to 36 w cm.sup.-2. Lamps of this design achieve high efficacy at relatively low power, i.e., below 30 watts.