| 摘要 |
The present invention is a fiber which is constituted by both a photonic crystal fiber having such a structure that holes are arranged in a quartz glass fiber and a quartz glass tube that has a cross section with a cyclic outer contour and that covers the outer periphery of the photonic crystal fiber with spaces therebetween and which is characterized in that the outer periphery of the photonic crystal fiber is in contact with the inside wall of the quartz glass tube at three or more positions. It is preferable that the photonic crystal fiber has a cross section with a cyclic outer contour, while the quartz glass tube has a cross section with a quadrilateral or triangular inner contour. Alternatively, the photonic crystal fiber may have a cross section with a quadrilateral outer contour, while the quartz glass tube may have a cross section with a cyclic or quadrilateral inner contour. |
