OPTICAL FIBER AND MANUFACTURING METHOD THEREFOR

To provide an optical fiber which effectively propagates illumination light and sufficiently suppresses irradiation unevenness by allowing an entire second core layer to directly propagate and supply the illumination light of a light source.SOLUTION: An optical fiber is provided, comprising a first core layer consisting of multiple cores capable of directly propagating light and a sheath layer integrally surrounding and covering the cores, and a second core layer integrally surrounding the first core layer and being capable of directly propagating the light.SELECTED DRAWING: Figure 1 【課題】第二コア層全体で光源の照明光を直接的に伝搬供給するようにすることで、効率的に照明光を伝搬させ、照射むらを十分に抑制した光ファイバーを得る。【解決手段】光を直接的に伝搬可能な複数本の芯と前記芯の周囲を一体で囲い被覆した鞘層とからなる第一コア層と、前記第一コア層の周囲を一体で囲いかつ光を直接的に伝搬可能な第二コア層とを有する光ファイバー。【選択図】図１