Green and red emissions in terbium and europium benzoic acids (TBA and EBA) incorporated poly methyl methacrylates (PMMA) are exhibited. Larger intensity parameters Ω2 (11.13×10-20 cm2) and Ω4 (13.15×10-20 cm2) of Eu3+ indicate a high inversion asymmetrical and strong covalent environment around lanthanide (Ln) ions and maximum emission cross section σem-max (2.45×10-21 cm2) for the dominant transition D50→F27 of Eu3+ reveals the effective photon conversion capacity in EBA incorporated PMMA. Color variation and fluorescence enhancement are validated to be originated from energy transfer and synergistic effect in TBA/EBA coincorporated PMMA system. The results indicate that Eu and Tb complexes incorporated PMMA with effective photon conversion hold great prospect in increment of lighting quality and enhancement of solar-cell efficiency employed in outer space.