A tunable Fabry-Perot (F-P) filter by using electro-optic polymer film is proposed. The electro-optic polymer is alkoxysilane dye (ASD)/SiO2-TiO2 hybrid material, whose electro-optic coefficient γ_(33) is about 5 pm/V. The wavelength tuning range of 3.8 nm under 400-V DC voltage and the nonlinear ch