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:
Jan. 15, 1991
Filed:
Sep. 08, 1989
Tetsu Takemura, Himeji, JP;
Hidetoshi Ichinose, Fujisawa, JP;
Keisuke Ohkubo, Himeji, JP;
Akihiko Sugitani, Takasago, JP;
Toshiyuki Okamoto, Takasago, JP;
Ushio Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A method for producing a fused silica envelope for use in a discharge lamp in which the inner surface of a fused silica tube is coated with a formulation containing titanium alcoholate and the coating treated by the steps including baking at a temperature of at least 1720.degree. C. to cause TiO.sub.2 to diffuse into the tube. The method results in a Ti concentration in a range of 1 .mu.m-10 .mu.m from the inner surface of the wall of the envelope is 0.5%-7% in terms of TiO.sub.2 and the product of the overall average Ti concentration and the thickness of the wall of the envelope ranges from 3.7% .mu.m to 42% .mu.m. During the baking step, the tube is shaped to include a bulb-like portion by inflating the silica tube.