| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical fiber preform manufacturing method which can clean an optical fiber preform having vacancy in a short time and certainly, and a vacancy optical fiber manufacturing method.SOLUTION: An optical fiber preform manufacturing method for manufacturing a vacancy optical fiber having at least hole extending longitudinally includes an optical fiber preform preparation process to prepare an optical fiber preform having at least one hole extending longitudinally, and a cleaning process to introduce cleaning liquid from one end of the optical fiber preform into the hole directly, clean the inside of the hole by passing the liquid, and exhaust the cleaning liquid from the end opposite to the end introducing the cleaning liquid. |
