| 摘要 |
PURPOSE:To maintain the specified polarization direction by providing two cores in one clad and providing polarization plane maintaining power to both cores. CONSTITUTION:The two cores are provided in one clad and the polarization plane maintaining power is provided to both cores. For example, a dual optical fiber 10 is twisted around the fiber axis. Then the cores pass alternately the inside and outside of the bend when the fiber 10 is subjected to bending and therefore the phase differences of the light generated by the bend are negated by each other and are not affected by the bend. The generation of the rotation for the polarization plane is thereby obviated and therefore the stable measurement result of high accuracy is obtd. |
