Contactless measurement of the electrical resistance per unit length of filaments
US5083090A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1990 |
| Grant date | Jan 21, 1992 |
| Priority date | — |
| Expiry date | May 31, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A non-contacting method of measuring the electrical resistance per unit length of a filament, such as a carbon-coated optical fibre, makes the filament the inner conductor of a co-axial transmission line and measures a propagation characteristic of that line. The transmission line may be divided into seven sections, with a signal injected on the second section, and a comparison of the resulting signals appearing on the fourth and sixth sections being used in a feedback loop to control the injected signal frequency in such a way as to hold constant either the relative amplitudes or the relative phases of the signals appearing at the fourth and sixth sections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.