phosphor samples were synthesized by a solid-state reaction method. The lattice parameter of the  phosphor samples was linearly decreased from 12.654 to , and the main emission wavelength was shifted from 501 to  with increase of the  ion concentration  from 0.05 to 0.50. The relative photoluminescence (PL) intensity under  excitation was increased with increase of the  from 0.05 to 0.25 due to the excitation band extended to the longer wavelength. However, when , the PL intensity was decreased due to nonradiative transitions among the  ions and the formation of  impurity phase. The Commission International de l’Eclairge chromaticity coordinates were also largely shifted from the bluish-green emitting region (, ) to the green emitting one ( = 2.414, = 0.658) by increasing the  from 0.05 to 0.50. The energy transfer from the  ion to the  ion enhanced the PL intensity of the  ion emission under near ultraviolet and blue excitation. The PL intensity of the  phosphor sample was higher by 24% than that of the  phosphor sample under  excitation.