| 摘要 |
PURPOSE:To increase the deposition rate of fine glass particles and to manufacture economically a perform for an optical fiber by arranging nozzles for feeding O2, H2 and O2 successively around a nozzle for feeding a gaseous starting material to form a multiply tubed burner and by burning said gases. CONSTITUTION:A multi-tube burner consisting of a plurality of concentric nozzles used in the manufacture of a preform for an optical fiber by a vapor axial deposition method is formed by arranging successively a nozzle n0 for feeding gaseous O2, a nozzle nH for feeding gaseous H2 and a nozzle n0 for feeding gaseous O2 around a nozzle nm for feeding a gaseous starting material for glass. Said gases are mixed and burned with the burner. The distance of diffusion required to react hot H2O, generated by the combustion reaction of O2 with H2, with SiCl4 or other gaseous starting material spouted from the central nozzle is shortened. The gaseous starting material reacts with hot H2O before it reaches a target, and the resulting fine glass particles are efficiently deposited on a starting rod in the axial direction. |
