Patent · US Active

Eddy current detection and compensation

US7957925B2 · kind B2 · utility

14Cited by

7References

34Claims

0Family size

Assignee

Northern Digital Inc. · CA

Inventors

John M. Nieminen · Waterloo, CA
Stefan Kirsch · Heidesheim, DE

Key dates

Filing date	Aug 23, 2010
Grant date	Jun 7, 2011
Priority date	—
Expiry date	Aug 23, 2030

Classification

Technology area (CPC A)Human Necessities
CPC primaryA61B2034/2051
WIPO fieldMedical technology
WIPO sectorInstruments

Abstract

A distortion compensation method includes determining an undisturbed phase for at least one of a first position indication signal and a second position indication signal. The method includes determining an undisturbed ratio that relates the amplitude of the first position indication signal at a first frequency to the amplitude of the second position indication signal at a second frequency. The method also includes determining a disturbed amplitude of the position indication signal and adjusting a position indication based on the disturbed amplitude and phase, the undisturbed amplitude ratio, and the undisturbed phase. The method further comprises determining a relationship between the eddy current phase of the first position indication signal and the second position indication signal.

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