| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical fiber for controllably taking out and distributing the light propagating in an optical fiber. SOLUTION: The optical fiber has plural regions 101, 103 having refractive indices varying from each other. At the time the light propagates along the longitudinal direction of the optical fiber, the light progresses from the region n1 of a certain refractive index to another region having a different refractive index n2 , is sufficiently deflected and is distributed along the longitudinal direction of the optical fiber from its flank. The light propagating in the optical fiber in the longitudinal direction position of the optical fiber where the change in the refractive index arises is efficiently deflected from the flank of the optical fiber toward the outer side of the optical fiber. The deflected light is refracted by the one or more refraction region, is condensed by a prism film 106 disposed on the flank on the exit side of the optical fiber and is effectively utilized. |
