Optical properties and zero photoelastic constant of ns{sup 2}-type metal cation containing oxide glasses

Zero photoelasticity and the relevant optical properties in binary RO–SiO{sub 2} (R = Sn, Pb) and R′{sub 2}O{sub 3}–SiO{sub 2} (R′ = Sb, Bi) and ternary Bi{sub 2}O{sub 3}–B{sub 2}O{sub 3}–SiO{sub 2} glasses were systematically studied. The zero photoelastic silicate glass leads to zero stress-induced birefringence, providing application to an optical lens, a filter, a beam splitter, and a fiber optic sensor without stress-induced birefringence. In this study, a variety of zero photoelastic binary silicate and ternary borosilicate glasses with optical bandgaps of 3.1–3.9 eV containing highly polarized ns{sup 2}-type cations are reported.