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:
May. 18, 1982
Filed:
Apr. 28, 1980
Applicant:
Inventor:
William D Meisburger, Los Altos, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G21K / ; H01J / ;
U.S. Cl.
CPC ...
2503 / ; 2503 / ; 313460 ;
Abstract
An electron lens having very low spherical aberration. The two electrodes of the lens, in the case of an immersion lens, and the outer electrodes in the case of a three electrode lens, have central openings (in the region of the optical axis) covered by a metallic thin foil or a fine mesh metallic screen curved in the general shape of a hyperbola. Equations and procedures are given for determining the exact shape of the curvature. A procedure is also disclosed for forming the metallic foil or screen section of the electrode to the desired shape.