PRODUCTION OF POROUS GLASS PREFORM FOR OPTICAL FIBER AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To stabilize the refractive index distribution of a porous glass perform by changing the direction of a rectifying plate arranged in a container and controlling the change in air streams due to the growth of a porous glass preform for an optical fiber. SOLUTION: A rectifying plate 11 is arranged on the tip side of a core burner 4 and a clad burner 5 installed parallel on the upper and lower sides in a container 1 and in the bottom of a flame 6 for forming a core part and a flame 7 for forming a clad part so that a rotating shaft 12 in the center in the width direction may face the horizontal direction. Both ends of the rotating shaft 12 are led through an axial sealing part 13 out to the outside of the container 1, and one end of the rotating shaft 12 protruding to the outside of the container 1 is connected to a motor 14 for rotating the rectifying plate 11. The direction of the rectifying plate 11 is then changed to control the change of air streams in the container 1 due to the growth of a porous glass preform 8.