OVER CLADDING METHOD OF MANUFACTURING OPTICAL FIBER

摘要

PURPOSE: A method for over cladding an optical fiber preform and a method for drawing an optical fiber are provided to easily perform an over cladding on an optical fiber preform and a glass tube, improve productivity in manufacturing the optical fiber preform, manufacture the preform having a high strength, prevent stress caused in a boundary surface, reduce a manufacturing time, and draw the optical fiber in a consecutive manner. CONSTITUTION: A furnace preheats or heats an oxygen/hydrogen burner and a glass tube. A carriage is vertically moved between a top chuck and a bottom chuck. A coupler is connected to a vacuum pump. A control part controls flow of the oxygen/hydrogen burner and rotation of the chucks. An optical fiber preform is fixed and leveled on the top chuck. A glass tube is fixed and leveled on the bottom chuck. The optical fiber preform is inserted into a shaft of the glass tube. The glass tube is pre-heated by the furnace, and heated by the oxygen/hydrogen burner until reaching a softening point. Air in a clearance between the optical fiber preform and the glass tube is vacuumized and the clearance is sealed to form a preform.