Manufacturing method of polarizing glass and polarizing glass article

摘要

There is provided polarizing glass having a high extinction ratio in a broad band. A manufacturing method of the polarizing glass containing elongated metal particles dispersed and oriented within glass includes an elongation step of forming mother glass after heat-treatment into a preform, of heating the preform at such temperature that the viscosity of the glass becomes about 1x10⁸ to 1x10¹⁴ poise, of applying stress of about 200 kg/cm² to 500 kg/cm² to the preform while moving the preform within an electric furnace with feeding speed of 10 mm/min. or less and of elongating the preform as an elongated sheet with pulling speed of 150 mm/min. or less by which an aspect ratio of halogenated metal particles contained in the preform becomes from 2 to 1 to 100 to 1 and a reduction step of reducing the elongated sheet for enough time for transforming at least a part of the halogenated metal particles into metal particles at temperature higher than the strain point temperature of the mother glass and lower than the transition point temperature of the mother glass.