| 摘要 |
PURPOSE:To prevent cladding loss by guiding incident light into only a core without propagation into cladding by forming an incidence end surface for light from a light emission source by only the core. CONSTITUTION:An optical fiber consists of a core 2 and cladding 3 covering the external circumference of the core 2, and in a light incidence end surface 5 facing a light emission source 4, the tip part 3a of the cladding 3 is tapered toward the light emission source 4 into a tapered surface 6, thereby preventing light from the light emission source 4 from entering the cladding 3. In the said light incidence end surface 5, a swelling part is formed atop of the core 2, thereby making the light from the light emission source 4 incident into the core 2 efficiently from the end surface 5. |
