This paper deals with the thermoluminescense of ZnS-Cu

Eu

Br ACEL powder phosphor

Thermoluminescence curves of the treated and untreated phosphor are compared before and after deterioration. After electroluminescence deterioration

the area enclosed by the thermoluminescence curve was reduced while no additional emission peak could be abserved.This may be coused by ion migration which results in decrease of shallow trap concentration.In comparison with the untreated phosphor

the treated phosphor has a smaller difference between the areas enclosed by thermoluminescence curves before and after eletroluminescence deterioration.It is supposed that since the Cu

2

S phase and the surface condition have been improved in the process of treatment

ion migration would be suppressed

the distribution of field strength and the condition of original injected-electrons would be changed and thus deterioration improved.