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:
Apr. 15, 2003
Filed:
Jul. 24, 2001
Fumio Hosokawa, Tokyo, JP;
Jeol Ltd., Tokyo, JP;
Abstract
A stigmator assembly capable of correcting even three-fold astigmatism without increasing the size of an electron microscope or the like in which the assembly is mounted. Values indicating control parameters A and &thgr; are set with control knobs and entered into a first arithmetic circuit. Values indicating control parameters A and &thgr; are set with control knobs and input into a second arithmetic circuit. The first arithmetic circuit calculates current values for producing a corrective hexapole field, using the entered control parameters A and &thgr; . The second arithmetic circuit calculates current values for producing a corrective quadrupole field, using the entered control parameters A and &thgr; . An adder circuit supplies control currents into coils, respectively, the control currents corresponding to the sums of the values calculated by the arithmetic circuits.