| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a manufacturing method which can make a quartz glass porous body for an optical fiber more steadily by reducing a defective soot cracking. <P>SOLUTION: In a manufacturing method of a quartz glass porous body for an optical fiber which comprises supplying at least a combustion gas, a combustion supporting gas and a glass raw material gas to a burner for forming a core part and a plurality of burners for forming a clad part, and depositing the glass fine particles produced in the flame onto a target, the method comprises controlling the fluctuation of maximum temperature of the surface of the quartz glass porous body by the flame of the first burner for forming a clad part not higher than 50°C between the length from the start of making of the quartz glass porous body to A-d to A+d, wherein A is the difference of the heights of the burner for forming a core part and the first burner for forming a clad part and d is the diameter of the flame spot of the first burner for forming a clad part. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
