Department of Inorganic Pigments and Glazes, Institute for Color Science and Technology
Ultra optical glasses are proposed for attaining noble glazes of high reflection and shine. In addition, these glasses can be used as semi-mirrors and optical instruments. In this reseach attempts were devoted mainly to introduce a glass system with the highest possible refractive index in which the highest reflection is desirable. Thus different amounts of heavy metal oxides modifiers, such as PbO and Bi2O3 were compounded with Ga2O3, as a glass former, and were melted to determine the stable glass regions in the corresponding three oxide glass system. Results suggested the most stable glasses were located in the eutectic region of the above oxides three phase diagram, where the melting was as low as 900OC. DTA measurements presented glass stabilities as the highest differences between the glass crystallinity and transition temperatures, `Tc-Tg`. Glass samples were moulded, cut and shaped into prisms, rods and narraw slides accuratly as required for the ultra optical propeties measurements by “Minimum angle of diviation of light in a prism” method. Refractive indices above 2.447 for yellow spectrum of 574 nm were achieved, i.e. higher than that reported for diamonds, i.e. 2.417. Dispersion property, as Abbe Number, was as low as 10 for the lowest content Ga2O3. Referring to the transmission bands in theses glasses, they could perform good optical nonlinearity, and be applicable in optical switching instruments.