DUAL CORE TYPE DISPERSION SHIFTING OPTICAL FIBER, DUAL CORE TYPE DISPERSION SHIFTING OPTICAL FIBER PREFORM, AND MANUFACTURE OF THE OPTICAL FIBER PREFORM

摘要

PROBLEM TO BE SOLVED: To restrain the generation of bubbles in the boundary part between a side core member and a clad member to prevent the increase in transmission loss and the reduction in yield by providing an inclination part slantingly lowering in refractive index to have an inflection point in the boundary between a side core and a clad. ;SOLUTION: This dual core type dispersion shifting optical fiber is formed of a center core 3, a side core 4 and a clad 2. AN inclination part having a refractive index slantingly reduced from the side core 4 to the clad 2 to have an inflection point is provided in the boundary between the side core 4 and the clad 2. The width W of the inclination part is set to 25-40% to the core diameter D. Since it has the inflection point 1, the refractive index is gently reduced toward the clad 2. In the refractive index distribution, the length D from the position of the inclination part showing the inflection point 1 to the clad 2 is preferably set to 60-90% to the width W of the inclination part.;COPYRIGHT: (C)2001,JPO