| 摘要 |
PURPOSE:To stably manufacture the titled fiber having an arbitrary refractive index distribution by forming a plurality of transparent pipes with methoxysilane as principal starting material through gel, putting one pipe with higher refractive index in other pipe, and heat uniting and drawing the pipes. CONSTITUTION:Liq. starting material 1 prepared by mixing methoxysilane as the principal component with a dopant and methanol, water or the like is poured in a cylindrical or circular container 2. The methoxysilane is hydrolyzed in the container 2 to produce gelatinous wet gel 3 of SiO2. By slowly drying the gel 3, the volume is reduced, and dry gel 4 is produced. The resulting gel 4 is heated in a heating container 7 to manufacture a sintered transparent pipe 5. By regulating the amount of the dopant contained in the liq. starting material 1 and using containers 2 different from each other in size, a plurality of transparent pipes 5 different from each other in refractive index and diameter are obtd. One pipe with smaller diameter and higher refractive index is put in other pipe with larger diameter and lower refractive index, and the pipes are united by heating and drawn. |
