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:
Aug. 26, 1980
Filed:
Mar. 28, 1979
Applicant:
Inventors:
Assignee:
Nihon Denshi Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
2503 / ; 250311 ;
Abstract
In a scanning electron microscope, an objective lens field is generated between a pair of deflecting coils and a specimen by an objective lens having upper and lower magnetic pole pieces. A supplemental magnetic pole piece is installed between said upper and lower magnetic pole pieces so that the half width of the objective lens axial magnetic field distribution is increased and the principal plane of the objective lens is positioned near the lower pole piece. By so doing, the spherical aberration coefficient of the objective lens is reduced and a high resolution scanning image is obtained.