| 摘要 |
PROBLEM TO BE SOLVED: To efficiently couple the laser light from a semiconductor laser with an optical fiber, to stabilize the wavelength, to obtain superior mass-productivity, and to obtain the optical fiber which is adaptive to high luminance. SOLUTION: The optical fiber 1, formed of a core 2 and a clad 3 covering the periphery of the core, is characterized by that the core diameter of the incidence end is larger than that of the projection end and smoothly decreases from the incidence end 11 to the projection end by being equal to that of the projection end and the tip part 12 of the incidence end is wedgelike having curvature in the length-direction section of the optical fiber and linear in the section orthogonal to the mentioned section. |
