| abstract |
Photochromic glass contains, by wt., 35-85 % TeO2, 0.5-10 % Er2O3, 0-30 (7-30) % PbO and/or 0-45 (15-40)% WO3, provided that PbO and WO3 contents are not both 0%. Used for modulation of radiation of wave-length near 479 nm, e.g. lasers; laser material carriers; optical data processing for electronic computers; flash light protection. Photochromic effect of desired magnitude and half-life time can be achieved by adjusting Er2O3 concn. In addn. to Er2O3, photochromic glass may contain a further suitable oxide of lanthanide series to modify photochromic effect, pref. 0.5-10 % Yb2O3 which acts as activator for Er2O3. |