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:
Dec. 03, 2002
Filed:
Apr. 23, 2001
Shoji Miyanaga, Takasago, JP;
Ushiodenki Kabushiki Kaisha, Tokyo, JP;
Abstract
A direct-current-lighting, ultra-high-pressure mercury lamp that is resistant to loss of transparency even after being lit for a long period, and has little wastage of electrodes and particularly the cathode tip, and also exhibits a long service life. The direct-current ultra-high-pressure mercury lamp includes a cathode and anode of tungsten facing each other within a quartz glass tube, and a cathode coil which is wrapped around the cathode. The cathode is composed of tungsten doped with potassium, and the anode is composed of tungsten having a purity of at least 99.99%. The cathode coil can also be advantageously formed of tungsten having a purity of at least 99.99%.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile