Eu~(2+) and Ce~(3+) are important rare earth ions with variable valences. There existtwo kind of transition emission, d-f and f-f for Eu~(2+). Eu~(2+) is a good candidatefor the activators of UV-visible tunable laser and luminescent materials due to itstransition characteristics. Ce~(3+) displays only d-f transition, which is different fromother rare earth ions. Because of the transition properties of Eu~(2+) and Ce~(3+), theyare used both as good activators and as efficient sensitizers. Spectral characteristics Eu ~ (2+) and Ce ~ (3+) are important rare earth ions with variable valences. There existtwo kinds of transition emission, df and ff for Eu ~ (2+) the activators of UV-visible tunable laser and luminescent materials due to itstransition characteristics. Ce ~ (3+) displays only df transition, which is different fromother rare earth ions. Because of the transition properties of Eu ~ (2+) and Ce ~ (3+), theyare used both as good activators and as efficient sensitizers. Spectral characteristics