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:
Mar. 10, 1998
Filed:
Jul. 25, 1995
Applicant:
Inventors:
Zhuomin M Zhang, Gaithersburg, MD (US);
Raju U Datla, Silver Spring, MD (US);
Leonard M Hanssen, Gaithersburg, MD (US);
Assignee:
The United States of America as represented by the Secretary of Commerce, Washington, DC (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
359350 ; 359888 ; 428457 ; 428697 ; 252587 ;
Abstract
A neutral-density optical filter has a dielectric substrate and a film costing essentially of copper and nickel. The film is preferably formed of Constantan, which is 55% copper and 45% nickel. The filter achieves a high optical density with a low spectral variation.