METHOD AND APPARATUS FOR PRODUCING GLASS PREFORM

• Main Authors: TANADA HARUYOSHI, HIRANO NOBUYUKI
• Format: Patent
• Language: English
• Published: 02.12.2004
• Edition: 7
• Subjects: CHEMISTRY; GLASS; MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES; METALLURGY; MINERAL OR SLAG WOOL

PROBLEM TO BE SOLVED: To provide a glass preform production method whereby the addition of fluorine is uniformly performed irrelevantly to the deterioration of a furnace core tube or the shape of a glass fine particle deposit; and an apparatus used therefor. SOLUTION: The glass preform production method comprises charging a glass fine particle deposit 2 into a furnace core tube 6 of a heating furnace 1, forming a gas atmosphere containing an additive, and adding the additive to the glass fine particle deposit 2 by controlling a heater 11 arranged in multiple steps around the furnace core tube 6. In the method, the surface temperature of the glass fine particle deposit 2 is measured, and the measured value is fed back to control the heater 11; thus, the heating temperature of the glass fine particle deposit 2 is uniformly controlled and the addition of fluorine is performed uniformly. COPYRIGHT: (C)2005,JPO&NCIPI