Method for producing glass preform for optical fiber.

摘要

A method for producing a glass preform, which method comprises forming a soot preform of glass fine particles comprising SiO<Sub>2</Sub> by flame hydrolysis or solution hydrolysis of a starting glass material and sintering the soot preform in an atmosphere containing at least SiF<Sub>4</Sub> to obtain a glass preform which is free from an increase in absorption due in absorption due to impurities and has sufficiently low attenuation of light transmission.