Patent ID: 6205281
Filing Date: 2001-03-20
Classification: C03B,C03C,G02B,H01S,Y02P

Abstract:
An optical article comprising:a transparent glass-ceramic core, said glass-ceramic core having substantially only one crystal phase, consisting essentially, in terms of cation percent, of:SiO.sub.2 20-40; AlO.sub.1.5 10-20; CdF.sub.2 19-34; PbF.sub.2 15-25; ZnF.sub.2 0-7; REF 3-10;wherein up to 5 mole % of CdS or 3 mole % of CdCl.sub.2 can be substituted for an equivalent amount of CdF.sub.2, or an equivalent amount of an oxide can be substituted for the fluoride; where REF is at least one of YF.sub.3 3-7, GdF.sub.3 3-7, and LuF.sub.3 4-15 and RE is at least one of Pr.sup.3+, Dy.sup.3+, and Er.sup.3+ ; anda transparent glass cladding, consisting essentially, in weight percent on an oxide basis, of:SiO.sub.2 25-35; Al.sub.2 O.sub.3 3-5; CdF.sub.2 12-16; PbF.sub.2 40-50; ZnF.sub.2 4-8; and Bi.sub.2 O.sub.3 0-10.