| 摘要 |
<p>PURPOSE:To enhance the magnetic field sensitivity without enlarging the shape and increasing dimensions, by winding an optical fiber having the Farady effect into a shape like a search coil and arranging this optical fiber on the outside circumference of a conductor. CONSTITUTION:An insulating supporting member 3 for fixing an optical fiber is arranged on the outside circumference of a conductor 1, and a search coil-shaped optical fiber 4 wound with a prescribed diameter is provided on the outside circumferential face of the insulating supporting member 3. Coils are so arranged that planes of coils are parallel with the conductor 1, and plural coils are cascaded so as to obtain a required sensitivity. The search coil-shaped optical fiber 4 is wound in several turns so that the length of one turn (circumferential length) is 2pi/DELTAB. The value DELTAB is the difference of propagation constant between two linearly polarized waves orthogonal to each other passing in the optical fiber 4. By increasing the number of turns of the coil 4, the length of the optical fiber is increased equivalently to enhance the magnetic field sensitivity.</p> |
