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:
Nov. 02, 2004
Filed:
Feb. 28, 2001
Yasunao Oyama, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
For realizing an optical member for vacuum ultraviolet with little absorption and with a low deliquescence nature and a low cleavage nature, a halide of an alkali metal such as Li, Na, Cs, or the like and a halide of any one of alkaline earth metals and other elements such as Ca, Sr, Ba, Mg, Zn, and the like are mixed in a ratio of 1:1, the mixture is sintered, and a fluoride crystal of AMF type perovskite structure is grown. The crystal is processed to fabricate a substrate of an optical member such as a lens, a mirror, a prism, or the like for excimer lasers. Alternatively, the crystal is used as an evaporation source to coat a substrate of an optical member therewith. It is thus feasible to obtain optical members with little absorption in the vacuum ultraviolet region and with an excellent durability.