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. 17, 1990
Filed:
Apr. 17, 1990
Applicant:
Inventors:
Noel S Poduje, Needham Heights, MA (US);
Roy S Mallory, Bedford, MA (US);
Assignee:
ADE Corporation, Newton, MA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
324663 ; 324690 ;
Abstract
A compensated capacitive probe system in which the probe and a guard ring are placed in the feedback path of an operational amplifier. An input signal is applied to the operational amplifier in combination with a portion of the guard signal. The resulting configuration compensates for stray capacitance at a measuring electrode of the probe and for the fact that the operational amplifier is other than mathematically ideal.