| 摘要 |
PURPOSE:To carry out a large amount of doping with a simple means, by dissolving a dopant in a liquid solvent, and impregnating the dopant solution in the glass soot layer prior to the convertion of the soot layer to transparent glass. CONSTITUTION:In the first step (A), a glass soot layer 2 is deposited to the outer circumference of the glass core rod 1 made of an SiO2 preform rod, by external deposition CVD process. Before converting the glass soot layer 2 to transparent glass, the glass rod 1 is immersed in a dopant 3 dissolved in a liquid solvent and contained in an immersion tank 4 to impregnate the dopant 3 into the glass soot layer 2 (the second step B). In the third step (C), the glass rod 1 is taken out of the immersion tank 4, and dried in a drying chamber 5. Finally, the glass rod 1 is set to a glass lathe, rotated, and heated with an oxyhydrogen flame burner 6 at a high temperature to convert the glass soot layer to a transparent glass (the fourth step D). |
