| 摘要 |
<p>A method of fabricating an optical fiber preform that can give stable and high deposition efficiency from the start to the end of the deposition when synthesizing a large size preform. When fabricating a preform by hydrolyzing a glass raw material gas in flame to generate glass particles and depositing the glass particles on a rotating starting material in the radial direction using a burner with a concentric multiple-tube structure having at least a plurality of small diameter combustion assisting gas-ejecting ports having the same focal length. L 1 is made greater than L 2 (L 1 > L 2 ) during an early stage of deposition and L 2 is increased in the cource of the deposition so that L 2 is greater than L 1 (L 1 < L 2 ), where the focal length is denoted by L 1 and the distance from the tip of the burner to a deposition plane on the starting material is denoted by L 2 .</p> |
