| 摘要 |
PURPOSE:To obtain a simple and small magnetic field sensor requiring no power, by providing the first and second superconductive loops, a superconductive cable and a magnetic flux detector. CONSTITUTION:Superconductive loops are formed so that the magnetic flux crossing the whole of said loops becomes 0. When the first superconductive loop 1 is inserted in a magnetic field H0 to be measured in this state, crossing magnetic fluxes PHI1 corresponding to the magnetic field H0 and the position and shape of the loop 1 are generated in the loop 1. Since all of the magnetic fluxes crossing the superconductive loop are held to 0, all of magnetic fluxes PHIall being the sum of the magnetic fluxes PHI2, PHI3 crossing a superconductive cable 2 and the second superconductive loop 2 become PHIall=PHI1+PHI2+PHI3=0. When the shape of the superconductive cable is devised so as to form PHI2=0, PHI3=-PHI1 is formed and a crossing magnetic flux reverse to the crossing magnetic flux generated in the system to be measured in a direction and equal thereto in an absolute value is generated in the loop 3. At the same time, the current proportional to the magnetic field to be measured flows to the superconductive loop 3. By detecting the current flowing to the loop 3 and the crossing magnetic flux PHI3 in a detection system using a magnetic flux detector 4, the crossing magnetic flux PHI1, in its turn, the magnetic field H0 can be determined.
|
