Polarizing glass and manufacturing method of polarized glass

A polarizing glass including elongated metal particles oriented in a uniform direction and dispersed, which are produced by a method which comprises:

• a preparing process to prepare a strip of glass base material containing metal halide particles precipitated therein;
• an elongating process to elongate said glass base material and said metal halide particles while heating said glass base material with heaters put around said glass base material, and drawing said glass base material to the longitudinal direction thereof with a drawing means set outside of said heaters along the longitudinal direction of said glass base material;
• and
• a reducing process to reduce said metal halide particles included in said elongated glass and elongated in said elongating process,
• wherein the powers of said heaters are controlled in said elongating process, so that said glass base material shrinks with the outlines of said elongated part thereof tilting against the longitudinal direction thereof by from 5 degrees to 20 degrees,
• wherein the variation of tilt angle of the polarizing axis of said elongated glass against the elongated direction of the elongated glass is 0.5 degrees or less.