PREPARATION OF GLASS BASE MATERIAL FOR SINGLE MODE FIBER

摘要

PURPOSE:To obtain the titled glass base material capable of facilitating the transparentizing, by flattening the heating temperature distribution of a burner for depositing fine glass particles of a part to be a clad in a direction crossing the radial direction. CONSTITUTION:A glass raw material for a core having a high refractive index and a combustion gas are mixed and burned by a core burner 1 at the center of the axis to be rotated and moved upward to deposit and grow fine glass particles and form a part 4 to be a core. When the part 4 to be core is formed to some extent, a glass raw material for forming a clad having a low refractive index and a combustion gas are mixed and burned by a clad burner 2' to deposit fine glass particles and form a part 5 to be the clad. The shape of the clad burner 2' is flattened in a direction crossing the radial direction of the growing base material, and the heating temperature distribution of the part 5 to form the clad by the burner 2' is flattened in the same direction as described above.