PURPOSE: To enable the detection of a weak magnetic field by arranging a means of radiating an electron beam to a target electrode and first and second electrodes for sensing a magnetic component at the right angle to the direction of the electron beam.
CONSTITUTION: A magnetroelectric converter has a vacuum body 1 in which a cathode 3 for emitting an electron beam 2, a control electrode 4, an acceleration electrode 5 and a target electrode 6 which an electron beam 2 irradiates are arranged while a pair of signal electrodes 7 and 8 are provided between the acceleration electrode 5 and the target element 6 to sense a magnetic field component at the right angle to the direction of the electron beam. With such an arrangement, when a magnetic field B is applied, the electron beam 2 is deflected toward the signal electrode 7 or 8 to cause a difference in the quantity of incident current flowing through the signal electrodes 7 and 8 thereby indicating the strength and the direction of the magnetic field B. Thus, even very weak magnetic field can be detected.
TAKEHANA YOSHITO
TSURUTA KOUJI
TANAKA YOSHIMITSU
