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:
Oct. 23, 2001
Filed:
Mar. 09, 1999
Katsushige Tsuno, Tokyo, JP;
JEOL Ltd., Tokyo, JP;
Abstract
There is disclosed an OMEGA energy filter comprising three magnetic field regions and producing small aberrations. The electron beam trajectory from the entrance window plane to the slit plane is continuously deflected into an omega-shaped form. Three magnetic field regions M,, M,, and M,having deflection angles &PHgr;, 2&PHgr;, and &PHgr;, respectively, are arranged in turn from the incident side. The deflection angle &PHgr; is set such that 102°_. . . &PHgr;_. . . 115°. The radius of curvature R,of the beam in the magnetic field region having the deflection angle 2&PHgr; is set less than the radius of curvature R,of the beam in the magnetic field regions having the deflection angle &PHgr;.