High-resolution X-ray imaging systems require materials with goodscintillation performances, especially X-ray absorption performance. Comparedwith powder phosphors display devices, those with transparent crystallinephosphors are very interesting due to their higher contrast and resolution forhaving no optical scattering, superior thermal conductivity as well as highdegree of uniformity and better adhesion. Europium-doped gadolinium oxide is apromising candidate due to its high density (7.62 g?cm-3), good light yield(18.5×103 photons/MeV), and the red emission of Eu3+ ion. The sol-gel method isone of the most important techniques for deposition of functional films, becauseit possesses a number of advantages over conventional film formation techniques,such as low processing temperature, easy coating of large surfaces, andhomogenous multicomponent oxide films. In X-ray imaging application, thethickness of the film is the most important factor for commercial use, which canincrease X-ray absorption of the film and then strengthen its luminescence yield.In the present work, transparent Gd2O3∶Eu3+ thick film was successfully preparedusing sol-gel method and spin-coating technique by choosing Ln2O3 (Ln=Gd, Eu) asraw materials, 2-methoxyethanol as solvent, PVP as adhesive and PEG200 as surfacemodifier. The film was homogeneous and crack free. The thickness of the filmcould achieve 1.5 μm after 2 times of coating, and its transmittance wasapproximately 80% in visible region. It was shown that PVP played an importantrole in film preparation, which could suppress stress and increase viscidity ofthe sol. In addition, the excitation, emission and decay time of the Gd2O3∶Eu3+scintillator film were studied. Their performances were quite good, which impliedthat the film would have promising applications in high-spatial-resolution X-rayimaging and flat panel display devices.properties(07dz22302)资助