Patent ID: 6512879
Filing Date: 2003-01-28
Classification: C03C,H01S

Abstract:
A phosphate-free, Er/Yb co-doped borosilicate glass composition, comprising, for 100 parts by weight made up of(i) 60 to 70 parts by weight of SiO2 or SiO2+GeO2 with SiO2 always representing more than 40 parts by weight, (ii) 8 to 12 parts by weight of B2O3, (iii) 10 to 25 parts by weight of M2O wherein M2O is at least one alkali metal oxide selected from the group consisting of the oxides; Na2O intervening at 0 to 20 parts by weight, K2O intervening at 0 to 20 parts by weight and Li2O intervening at 0 to 10 parts by weight, (iv) 0 to 3 parts by weight of BaO, (v) 0.01 to 5 parts by weight of Er2O3, (vi) from 0.1 to 12 parts by weight of Yb2O3 and from 0 to less than 5 parts by weight of F; and within which the boron atoms are of tetrahedral spatial coordination.