The present project will focus on the development of novel doped oxide glasses, which have down-conversion luminescent property and can be used to enhance the solar cell efficiency by broadening the solar spectrum for photovolt effects. Compared with powder, glass is more suitable for practical application, because it is transparent and easy to manipulate. Furthermore, oxide glass has proved to be suitable host materials for luminescence with high stability. For the high energy part of the solar spectrum, there are two ways to use it more efficiently: PL and DC. Compared with PL, DC takes place via a two-step emission process, which allows more than one photon to be generated for each incoming photon. Thus, the quantum efficiency of DC can reach 200% in theory. DC layers are incorporated above existing solar cells. No modification of the active layer is needed. In addition, different from UC, DC can be a linear process, suggesting that it will be easier to gain a performance advantage using the sun as the illumination source. Although the applications of UC in lighting have been researched for decades, the reports about its application on the efficiency enhancement of the solar cell are relatively few.