摘要 |
A photochromic glass having colorant incorporated in the glass composition to impart a permanent tint, and having its chromaticity point shifted from the blue-green side toward the red side of the white point in the CIE chromaticity coordinate system, and a method of producing such article by heating the article for a sufficient time, and at a sufficient temperature, in a dilute, hydrogen-containing atmosphere to so move the chromaticity point.
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