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. 31, 1993
Filed:
Dec. 02, 1991
Akira Yonezawa, Tokyo, JP;
Seiko Instruments Inc., Tokyo, JP;
Abstract
An electron beam device having a single pole electromagnetic objective lens whose pole top face is positioned in front of a sample as viewed from the side of an electron beam source. A secondary electron detector is provided in the vicinity of the pole top face of an inner cylinder of the objective lens. The objective lens has a circular cylindrical or conical shape at the top of the objective lens and the vertical angle of the circular cylindrical or conical shape is 45.degree.-90.degree.. The working distance between the top of the objective lens and sample is less than 6 mm. It is possible to survey the sample with a resolving power corresponding to a dimension about one-half that of the prior art under low accelerating voltage conditions.