Abstract: An optical CuO-bearing, alkali- and alkaline-earth rich phosphate glass with relatively high elongation (at 20.degree.-300.degree. C. from 110.times.10.sup.-7 grd.sup.-1 to 138.times.10.sup.-7 grd.sup.-1) and a transformation range .ltoreq.380.degree. C., with substantially improved transmission in the UV to blue range of the spectrum (UV-transmission at .lambda.=350 nm between .gtoreq.69% and .gtoreq.83%) and a very strong absorption in the red region of the spectrum (IR-absorption at .lambda.=700 nm between .ltoreq.2% and .ltoreq.12%), consisting essentially of the following synthesis/composition, in wt. %: P.sub.2 O.sub.5 65-70%; SiO.sub.2 0-0.75%; B.sub.2 O.sub.3 0-2%; A.sub.2 O.sub.3 2.5-6%; R.sub.2 O (alkali metal oxides) 11-17%; BaO 3-9.5%; CeO.sub.2 0.45-2.0%; CuO 2.55-6.55%; Cl.sup.- 0.15-0.75%; F.sup.- 0.25-1.50%; refining agent 0.10-2.00% with .SIGMA.CeO.sub.2 +Al.sub.2 O.sub.3 +BaO+CuO.gtoreq.8.5 and .SIGMA.R.sub.2 O=F.sup.- +Cl.sup.- .gtoreq.21.

Abstract: Low alkali, high phosphate and high Al.sub.2 O.sub.3 content glasses are described which are highly suitable for optical colored and filter glasses. They exhibit a glass transformation temperature Tg>450.degree. C. and have the following composition, in percent by weight:______________________________________ P.sub.2 O.sub.5 71.0-76.0 SiO.sub.2 0.25-2.5 B.sub.2 O.sub.3 2.4-3.75 Al.sub.2 O.sub.3 8.6-11.6 R.sub.2 O (alkali oxide) 1.25-6.5 CaO 0.5-1.65 MgO 2.0-3.5 Refining Agent 0.2-0.6 CeO.sub.2 0.1-0.4 F' 0.2-0.4 and CuO 1.0-10.0.