METHOD FOR MANUFACTURING RAW MATERIAL OF OPTICAL FIBER

摘要

PURPOSE: A method for manufacturing a raw material of an optical fiber is provided to reduce a time for manufacturing an optical fiber by condensing and closing the first raw material and the second sleeve tube simultaneously. CONSTITUTION: The first raw material(11) and the second sleeve tube(12) are installed on a vertical lathe. The first raw material(11) and the second sleeve tube(12) are rotated to the same direction on the vertical lathe. The first raw material(11) is fixed to the first dummy tube(14a) and on an upper chuck of the vertical lathe. The second sleeve tube(12) is fixed to the second dummy tube(13a) and on a lower chuck of the vertical lathe. A gas supply tube is installed on an upper side of the vertical lathe. A vacuum pump(16) is installed on a lower side of the vertical lathe. A heating portion(20) is installed on an outer circumference of the second sleeve tube(12).