**Table 3.**

*Characteristic temperature of tellurite glasses.*

75TeO2-20ZnO-5Na2O [43] system increases the ΔT value from 118 to 150°C, while 1 wt% Er2O3 introduced to 90TeO2-10P2O5 [44] system decreases the ΔT value from 147 to 101°C. Furthermore, the concentration of the rare earth ion has a significant influences on the ΔT value of the 75TeO2-20ZnO-5Na2O [45] glass system.
