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. 15, 1992
Filed:
Nov. 19, 1991
Applicant:
Inventors:
Miyoko Watanabe, Yokohama, JP;
Kuniyoshi Tanaka, Yokohama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
250306 ; 250307 ;
Abstract
A probe arranged to oppose a sample is coupled to a driving portion constituted by an actuator capable of obtaining a large expansion/contraction amount and an actuator capable of obtaining a small expansion/contraction amount. In order to keep the gap length between the sample and the probe constant, a first gap length control system drives the actuator and a second gap length control system having a driving time constant smaller than that of the first gap length control system drives the actuator in response to changes in gap length between the sample and the probe.