| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical fiber preform precisely measurable a refractive index distribution thereof and a manufacturing method of the optical fiber preform. <P>SOLUTION: An optical fiber includes a core region 1, an inner cladding region 2 surrounding the core region 1, a trench region 3 surrounding the inner cladding region 2, and an outer cladding region 4 surrounding the trench region 3. The optical fiber includes a refractive index varying region 10 provided between the inner cladding region 2 and the trench region 3 whose refractive index gradually increases toward the inner cladding region 2 from the trench region 3 side. <P>COPYRIGHT: (C)2012,JPO&INPIT |
