| 摘要 |
PURPOSE:To measure safely and easily a magnetic field of a part which is narrow spatially by providing a detecting part formed by a polarizer and a Faraday rotary element, etc., on the end part of an optical fiber. CONSTITUTION:A detecting part formed by a polarizer 2, an yttrium-iron-garnet 3 of a Faraday rotary element, a reflecting film 4, etc. is provided on the other end of an optical fiber 1 which makes a light source light incident and also emits a detecting light to a photodetector, and a magnetic field is measured by a linear polarized light whose plarizing plane is rotated in accordance with a magnetic field which propagates the fiber 1, is reflected by the film 4 and propagates the fiber 1 in the opposite direction. According to this constitution, a magnetic field of a part which is narrow spatially can be measured safely and easily without being influenced by an external noise. |
