Structural, electrical, and optical properties of the polycrystalline films of VO2, V2O5, and mixtures of these two oxides are presented. Resistivity change by a factor larger than 103 accompanying the semiconductor-metal phase transition in the VO2 films is reported. A significant contrast in optical transmittance for the two phases of VO2 is observed. High temperature resistivity and optical transmittance of the V2O5 films are shown. Values of the temperature coefficient of resistance in some of the VO2 films in their semiconducting phase and in some of the V2O5 films are as high as 5.2 and 4% per degree Celsius, respectively. Phase switching properties of the VO2-V2O5 films are described. Applications of the fabricated films include optical switches and bobmetric-type light detectors.