| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical fiber preform at a low cost in which hydroxy group concentration is reduced, and which is suitable for making an optical fiber which allows multiple-wavelength transmission over a broad wavelength band, and to provide a manufacturing method therefor. <P>SOLUTION: In the optical fiber preform 10 having a center glass rod 11 and an outer layer 12 formed in its outer periphery, when the radius of the center glass rod 11, the radius of the optical fiber preform 10, and the maximum value of the hydroxy group concentration in the vicinity of the boundary between the center glass rod 11 and the outer layer 12 are defined as r<SB>a</SB>(mm), r<SB>b</SB>(mm), and c (ppm), respectively, the optical fiber preform 10 is manufactured while satisfying following inequality: 0.002<r<SB>a</SB>/r<SB>b</SB>/c<0.01. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
