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. 18, 1999
Filed:
Oct. 07, 1997
Ushiodenki Kabushiki Kaisha, Tokyo, JP;
Abstract
A high pressure mercury ultraviolet lamp with high dimensional accuracy in which the emitter material during lamp operation is prevented from spraying and being deposited on the wall of the discharge vessel and the UV radiation transmission factor is prevented from being reduced is achieved by the fact that at least one of a group of halides which consists of halides of yttrium, lanthanum, cerium, dysprosium, gadolinium and thorium and at least one of a group of halides which consists of halides of alkali metal elements are filled at a filling ratio in the range from 1:4 to 1:20 to one another as a molar fraction. This also yields the same action as the application of emitter material to the upholding parts of the electrodes. Furthermore, high dimensional accuracy can be ensured by the measure by which the discharge vessel is made of a translucent ceramic, such as YAG.