OPTIC GLASS Russian patent published in 1995 - IPC

FIELD: production of photographic lens. SUBSTANCE: proposed glass contains (mass % ): phosphorous oxide 14-40, boron oxide 0.4-16, lead oxide 34-54, lithium oxide 0.2-2.3, potassium oxide 0.3-5.5, antimony oxide 0.5-6, and at least one oxide of the following: niobium oxide, aluminium oxide, lanthanum oxide, their quantities being respectively 1-20, 0.5-2, 0.5-2. Additionally proposed glass may contain boron oxide or tungsten oxide or germanium oxide, their quantities are 2-13, 5-14 and 2.5-5 respectively. Light transmission of 1 cm layer at wavelength 400 nm is 35-98 %. EFFECT: improves quality of glass. 2 cl, 1 tbl