Effect Of Expansion Coefficienton The Quanlitry Of The Optical Glass

Optical glass is a kind of material which has a structure between solid and liquid. In the molding process of the molding mixture, optical glass does not shrink uniformly, the crucial factor is the expansion coefficient (especially the expansion coefficient around transformation temperature Tg) of the glass which affects the appearance and rate of fine production directly. Because the expansion coefficient of molten glass is larger than elastic state glass by a factor of 2 to 4, even 5, after molding process, the molten glass is refrigerated to form elastic glass at the transformation temperature Tg, nonuniform shrink of the products occur.In this paper, the influence of the expansion coefficient to the production quality in the molding process is discussed and some views are advanced according to the quality problems of practical production. If the negative affects in the molding process caused by expansion coefficient, the quantity and quality of the optical glass will be largely improved.