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CaO-MgO-B2O3-SiO2 glass co-doped with Eu2+, Dy3+ was prepared, which showed the Long lasting phosphorescence. The luminescent properties of this photoluminescence glass had been studied systematically. The main emission peaking at 476nm was ascribed to the 4f5d→4f transition of Eu2+ in glass matrix. The optical absorption spectra of the samples fabricated under the ambient and reducing atmospheres were measured separately. The sample fabricated in the ambient atmospheres was transparent in wavelength region from 340nm to 1μm. While the samples fabricated in the reducing atmosphere a strong absorption band was observed from 350 to 450nm, and the peak was at the 375nm. This band could be assigned to the absorption of Eu2+ ions. The excitation spectra of the sample fabricated in the reducing atmosphere was measured. A strong peak at 396nm and a weak peak at 439nm were observed. They were ascribed to the transitions of Eu2+ ions. The results were conformed to the conclusion of the absorption spectrum. The afterglow decay process could be divided into two stages. One is an instant attenuation, and the other is a slow. Incorporation of rare ions Eu2+ and Dy3+ into glass matrix could largely change the long afterglow properties of the glass. The analytical results indicated that the co-doped Dy3+ ions acted as hole-trap levels and captured the free holes. It resulted in the property of long lasting phosphorescence of CaO-MgO-B2O3-SiO2 glass co-doped with Eu2+, Dy3+.
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