| 摘要 |
PURPOSE:To control easily the composition of a laminate and to manufacture the titled base material with high safety and reproducibility by preparing sooty starting materials having different refractive indexes, accumulating them in layers, and vitrifying the resulting laminate by heating at a high temp. CONSTITUTION:SiCl4 and GeCl4 fed from a starting material feeder 1 are vaporized and passed through an oxyhydrogen flame 3 blown from a burner 2 at a high temp. to deposit soot S on a target 4. The deposited soot S is scraped away with a quartz rod 5 and recovered in a container 6. Sooty starting materials S thus prepd. are successively accumulated in layers on a flat quartz plate B through each nozzle A so that the GeO2 content is gradually increased. The number of the layers is about 80-100 in general. The resulting sooty laminate is heated to a high temp. such as 1,500-1,600 deg.C with a heater 11 in a furnace 10, and the furnace 10 is evacuated in the direction of an arrow to make the laminate transparent. This transparent laminate is rolled into a pipe with a working machine, and the pipe is made solid with a burner 60 to form a reformed fiber 70 for an optical fiber. |
