| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a glass preform for optical fiber by which non-zero dispersion shift optical fiber having desired wavelength dispersion property can be manufactured with high yield. <P>SOLUTION: The method has a depositting step for making glass fine powder deposited body on the outer periphery of a starting rod, a drawing out step for drawing out the starting rod, a transparentizing step for making a transparent glass tube material by heating the glass fine powder deposited body, an etching step for etching a center hole surface, a solidifying step for making a solid glass preform by decompressurizing and heating the inside of the transparent glass tube material, in the depositting step the glass fine powder deposited body is made such that the difference of refraction index to the clad part increases from Δ0 to Δ1 from 0 to R0 in the radial direction from inside to outside, the difference of refraction index decreases from Δ1 to Δ2 from R1 to R2 in the radial direction, the difference of refraction index increases from Δ2 to Δ3 from R3 to R4, and the difference of refraction index decreases from Δ3 to Δ4 from R4 to R5, the etching step is carried out in the range where etching does not reach R0. <P>COPYRIGHT: (C)2012,JPO&INPIT |
