| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a rare-earth element-added optical fiber preform without peel-off of a glass particle layer containing the additives such as the rare-earth element during a production process. SOLUTION: This method comprises depositing the glass particle layer on the inner wall of a quartz pipe by applying an MCVD (modified chemical vapor deposition) method, immersing the resultant deposited layer in a solution containing the rare-earth element to obtain the glass particle deposited layer containing the rare-earth element, drying to remove a remaining water, making transparent and colapsing to produce the objective optical fiber preform. In this case, by performing the drying process at lower than 90°C under a reduced pressure or at a temperature of normal one to lower than 90°C under the reduced pressure, the peel-off of the glass particle layer from a glass layer in the drying and transparentizing processes can be reduced. COPYRIGHT: (C)2003,JPO |
