| 摘要 |
PROBLEM TO BE SOLVED: To surely prevent the occurrence of the liquid leak and the run of the core material in the vicinity of the calking section or the unplugging of a sealing plug or deviation and to maintain the optical transmission function over a long time by forming a film or a layer using the material having adhesiveness on the side surface of the sealing plug. SOLUTION: The timer side of a tubular clad 1 is filled with a transparent and liquid core 2 having the refractive index which is larger than the refractive index of the clad 1 and the both side opening sections of the clad 1 are plugged in by sealing plugs 3. The both side outer peripheral sections of the clad 1 are fitted with and covered by tubular metallic sleaves 4. Calking sections 5 of the sleaves 4 are calked and formed and the both side outer peripheral sections of the sleaves 4 are pressed and deformed. Moreover, a coating film 30 is formed over the outer peripheral surface of the plug 3. The plug 3 of the light incident side is formed from a transparent material. The light beams made incident from the plug 3 are transmitted to the core 2, reflected by the clad 1, transmitted to the other side direction of the core 2 and emitted from the other plug 3. |
