Current measuring magnetic field sensor having magnetooptic element with its easy axis of magnetization at right angles to the magnetic field generated by the current

摘要

The magnetic field sensor is described for sensing the magnetic field, which comprises a light source part, a magnetic field detection part which contains a magnetooptic element consisting of a magnetic materials having a magnetooptic effect, and a light measurement part which measures the light that has been radiated from the light source part and has passed through the magnetic field detection part, is characterized in that the magnetooptic element is arranged such that its easy axis of magnetization is at substantially right angles to the direction of the magnetic field to be measured. The sensor can measure in a wide range of magnetic field with a high degree of accuracy and high sensitivity.