| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for manufacturing such a glass preform having an end shape suitable for fiber drawing as is capable of reducing rapidly the eccentricity of an optical fiber at the beginning early stage of the fiber drawing and of shortening the region of the unsteady portion, and to provide a method for manufacturing an optical fiber. <P>SOLUTION: The glass preform having a straight body effective part with an average outside diameter D and having a taper part at one end of the above straight body effective part, is characterized in that this glass preform, when installed on a fiber drawing apparatus, has the ratioδ/D expressed by the relation:δ/D≤0.03, whereinδis the taper part distortion which is expressed by the maximal value in such displacement values of the central line of the glass preform as are between the direct body effective part end from the taper part and the distortion evaluating end of the taper part, and D is the average outside diameter. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
