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:
Sep. 24, 1985
Filed:
Oct. 08, 1981
Mamoru Nakasuji, Yokohama, JP;
Hirotsugu Wada, Tokyo, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
An electron beam exposure system has first and second apertures through which is passed an electron beam emitted from an electron gun. A rectangular image formed by superposition of the images formed by the first and second apertures is projected onto a target plane through a third aperture by condenser lenses and projection lenses. When a crossover of the electron beam drifts in the direction perpendicular to the axis of the lens system, the current of the electron beam projected on the target plate decreases. The electron beam current is detected by a faraday cup, and the locus of the electron beam is corrected by a coil assembly interposed between the second and third apertures so that the faraday cup may detect the maximum beam current.