Thermal stability and frequency up-conversion properties of Er3+... ... emission was discussed. The result shows that the obtained oxyfluoride tellurite glass 68TeO2-15BaF2-5SrF2-10LaF3-2KF has a good thermal stability ('Delta'T = 153.6 Celsius degree) and strong up-conversion green emissions around 527 nm and 549 nm and red ...