Variable frequency magnetic field device employing multiple antennae for measuring the surface impedance of a material
US5086274A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 11, 1990 |
| Grant date | Feb 4, 1992 |
| Priority date | — |
| Expiry date | Jun 11, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A surface impedance measurement device comprises a transmitting antenna producing a magnetic field in the area surrounding a material to be tested and a receiving antenna receiving the magnetic field. An electric voltage wobbled in frequency is applied to the transmitting antenna, and a circuit measures the voltage at the terminals of the second antenna. For the antennae to be applied on the same side of the material to be tested and of which the surface impedance is to be measured, the antennae are superposed by the intermediary of a dielectric wedge in a compact probe. The impedance measurements are then independent of the dimensions and geometry of the material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.