| 摘要 |
PURPOSE:To always execute the magnetic field source estimation which scarcely causes an error by providing an abnormality detecting means for monitoring the respective operating states of plural SQUIDs, and using a signal of the remaining SQUID except the SQUID whose operation is decided to be abnormal as data for estimating a magnetic field source. CONSTITUTION:An abnormality detecting circuit 2 expresses whether an operation of a SQUID is abnormal or not by '0' and '1', and an output of the abnormality detecting circuit 2 is added as a code to a digital value obtained by A/D-converting an output of a SQUID fluxmeter, and inputted to a computer 3. Subsequently, In the computer 3, this code is detected, so that data having the code for showing abnormality is not used for a calculation for estimating a magnetic field source. In such a way, an estimation error can be prevented in advance, and reliability of the device can be improved. |
