OPTICAL GLASS Russian patent published in 2009 - IPC C03C3/87 

FIELD: chemistry.

SUBSTANCE: glass has the following composition: SiO₂ in amount of 35 to 70 wt %, Al₂O₃ in amount of 17 to 35 wt %, P₂O₅ in amount of 3 to 17 wt %, Li₂O in amount of 0 to 6 wt %, MgO in amount of 0.5 to 4 wt %, ZnO in amount of 0.5 to 3 wt %, CaO in maximum amount of 1 wt %, BaO in maximum amount of 0.5 wt %, TiO₂ in amount of 0.5 to 6 wt %, ZrO₂ in amount of 0.5 to 3 wt %, Na₂O in amount of 0 to 1 wt %, K₂O in amount of 0 to 1 wt %, clarifiers (As₂O₃, Sb₂O₃) in maximum amount of 1 wt % and other admixtures in preferred amount of ≤500 parts/million.

EFFECT: design of optical glass which is suitable for cheap production of transparent elements with a particularly large thickness, with maximum transparency in the wavelength range from 550 to 750 nm and with thermal expansion coefficient of the order 3×10^-6/K.

12 cl, 1 ex, 1 dwg