LARGE SIZED QUARTZ GLASS TUBE, LARGE SCALE QUARTZ GLASS PREFORM, PROCESS FOR MANUFACTURING THE SAME AND QUARTZ GLASS OPTICAL FIBER.

摘要

A quartz glass tube, produced by mechanically processing a natural/synthetic quartz glass mother material, having 50 - 300 mm phi in outer diameter, from 1.1 to 7 in outer to inner diameter ratio, 10 mm or more in thickness and 2% or less in thickness error; a large-scale quartz glass preform integrally combining the large-sized quartz glass tube with a core glass rod for an optical fiber using a rod-in-tube technique; and a method for manufacturing a large-scale quartz glass preform performing the mechanical processing with a high precision machine, i.e., integrating a core rod for an optical fiber under a rod in process with a quartz glass tube, a tube diameter of which is controlled by heating, hot drawing or hot drawing with pressure by using a tool-free drawing method.