| 摘要 |
<p>PURPOSE:To enable measurement high in measuring accuracy without receiving the effect of an external magnetic field and to attain miniaturization and wt. reduction, by a method wherein hole parts are provided to both end parts of an iron core through which a conductor pierces and a Faraday effect element is arranged on the axis passing through both hole parts and the emitting and incident parts formed to the end parts are arranged to one hole part while a reflecting part is arranged to the other hole part. CONSTITUTION:Holes 18 are provided to both end parts forming a gap of an iron core 14 so as to allow the axes of both holes to coincide and an optical magnetic field sensor 17 is arranged so as to communicate the hole parts at both end parts. The light passing through an optical fiber from a light emitting part 6 to reach the optical magnetic field sensor 17 comes to a linear polarized light having a small expanse by a lens 17a and a polarizer 17b to be incident to a Faraday effect element 17d and said linear polarized light is turned back and reflected by a corner cube 17c having a plane-of-polarization preserving reflecting film provided to one end thereof while the plane of polarization is preserved to transmit through the Faraday effect element 17d toward the gap direction of the iron core 14. A magnetic field changes in the gap of the iron core 14 corresponding to the value of the current flowing through a conductor 2. Therefore, light having magnitude dependent on the rotation of the plane of polarization passes through an analyser 17a to reach a light receiving part 12.</p> |
