Absolute property measurement with air calibration
US6188218A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1998 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Oct 29, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/72
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An instrument and method for providing accurate and reproducible measurement of absolute properties of a material under test without using conductivity or crack calibration standards. The instrument has a sensor designed to minimize unmodeled parasitic effects. To accomplish this, the sensor has one or more of the following features: dummy secondary elements located at the ends of a primary winding meandering, setting back of the sensing element from a connecting portion of the primary winding, or various grouping of secondary elements. The sensing elements of the sensor can be connected individually or in differential mode to gather absolute or differential sensitivity measurements. In addition, the instrumentation is configured such that a significant portion of the instrumentation electronics is placed as close to the sensor head to provide independently controllable amplification of the measurement signals therein reducing noise and other non-modeled effects.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.