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:
Feb. 06, 1996
Filed:
Mar. 14, 1994
Donald R Sadoway, Belmont, MA (US);
Kevin G Rhoads, Andover, MA (US);
Naomi A Fried, Cambridge, MA (US);
Susan L Schiefelbein, Boston, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
An apparatus and method for measuring electrical parameters of a medium such as electrical conductivity and dielectric constant between a pair of electrodes are disclosed. The medium can be a liquid, gas, powder, etc., and the electrodes can be coaxial metallic circular cylinders. To compute electrical conductivity, the device is immersed in the medium to an immersion depth and the conductance across the electrodes is determined. The measurement is repeated at at least one additional immersion depth. By obtaining a differential conductance measurement with respect to the immersion depth, the effects of fringe conductances are eliminated from the measurement. The device can also be used to determine dielectric constant of the material by obtaining a differential capacitance measurement with respect to immersion depth. The device need not be calibrated by performing resistance measurements in a known standard solution. Also, because the electrodes can be purely metallic and include no dielectric material, the device can be used to perform measurements in highly corrosive media whose compositions would be altered upon contact with dielectric materials.