Patent · US Expired

Apparatus for capacitive electrical detection

US6420882B1 · kind B1 · utility

10Cited by

4References

43Claims

0Family size

Assignee

Sentech, Inc. · US

Inventors

Bjørn Engebretsen · Nesoddtangen, NO
Jon Morten Halleraker · Oslo, NO

Key dates

Filing date	Nov 12, 1999
Grant date	Jul 16, 2002
Priority date	—
Expiry date	Nov 12, 2019

Classification

Technology area (CPC G)Physics
CPC primaryG01N27/226
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

Apparatus for capacitive electrical detection or measurement relating to a medium, comprising at least one electrode having a given surface extension and an oscillator circuit the output frequency of which is a function of the capacitance being associated with the electrode and the dielectric constant of the medium, and is taken as a basis for the detection or measurement. The effective spacing of the electrode from a counter electrode or from earth is of the same or a substantially higher order of magnitude as seen in relation to the surface extension of the electrode. A conductor connecting the electrode to the oscillator circuit has a length that is a small fraction as seen in relation to the surface extension of the electrode.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.