| 摘要 |
PURPOSE:To achieve a higher sensitivity by correcting the output of a SQUID magnetometer composing a main magnetism detecting section with an detection output from separate detection of angle deviation and other noise components pertaining to a magnetometer used in the detection of an abnormal magnetic object buried in the earth magnetism, for example, drum cans, sunk ships and unexploded shells. CONSTITUTION:The direction (Z direction) of a coil bobbin 1 vertical to the plane of a main coil C1Z is directed roughly to the direction of earth magnetism HF. The magnetism detection force outputted via a magnetism detection circuit of an SQUID magnetometer from the main coil C1Z is applied to a terminal t1Z of an arithmetic circuit as illustrated. Magnetic fields caught with coils C1X and C1Y arranged on the plane perpendicular to the main coil are also outputted via the magnetism detection circuit of the SQUID magnetometer and applied to terminals t1X and t1Y to effect correction for deviation and oscillation from the direction of the earth magnetism. On the other hand, differential outputs of differential coils C2Z, C3Z, C2X.C3X and C2Y.C3Y each arranged parallel with the coils C1Z, C1X and C1Y are applied respectively to terminals t23Z, t23X and t23Y to correct effect due to nearby magnetic body. |
