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:
Jun. 04, 1985
Filed:
Oct. 17, 1983
Thomas L Bohl, Madison, OH (US);
Richard C Ciammaichella, Newbury, OH (US);
The Babcock & Wilcox Company, New Orleans, LA (US);
Abstract
An arrangement for isolating an optical surface from a contaminating environment utilizes concentric inner and outer tubes defining an annular purging space therebetween. The inner and outer tubes are both open ended with the open ends facing the contaminating environment. The optical surface is positioned in the inner tube and is spaced from the open end of the inner tube. The inner tube is made of porous material and the space is supplied with a purging gas so that at least some of the purging gas filters into an inner space of the inner tube to prevent an aspiration of contaminants into the inner tube from the open end thereof. A preferred porosity range of 1 to 40 microns is selected for the inner tube which preferably has a length to diameter ratio of from about 5 to 1.