Patent ID: 6949926
Filing Date: 2005-09-27
Classification: A61B,G01R

Abstract:
1. A biomagnetic measurement apparatus comprising: at least one magnetic sensor having a superconducting quantum interference device (SQUID) that detects a magnetic field generated from a subject to be tested; a cryostat for holding the SQUID at a low temperature; a fluxmeter operation circuit of the SQUID; and a computer for collecting an output signal of the fluxmeter operation circuit, wherein the fluxmeter operation circuit comprises: an integrator for integrating a magnetic field signal output detected by the SQUID; a filter for removing a direct-current component from the output of the integrator; and lock release detection means for detecting the release of the magnetic field lock by judging whether the output of the integrator that has been passed through the filter is substantially zero.