Method and apparatus for detecting and locating a selected non-metallic material in a detection region
US5177445A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 19, 1991 |
| Grant date | Jan 5, 1993 |
| Priority date | — |
| Expiry date | Jun 19, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/885
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Particular non-metallic materials are detected by a recognition of the way in which their electrical properties vary with the frequency of an applied alternating electric field. In one method a body being tested is subjected to electromagnetic radiation at each of a plurality of different frequencies, the pattern of variation of the body's reflectivity is evaluated and compared with stored information on the conductivity/frequency characteristic of the non-metallic material to be deleted. In another method a body being tested is subjected to a burst of electromagnetic energy and a measurement is made of the time taken for the body to retransmit energy absorbed from the burst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.