A device of liquid crystal display of liquid crystal display for increasing aperture ratio and viewing angle thereof is disclosed. The device comprises a thin film transistor array substrate having a first polarizer on a bottom side, a phase retardation dielectric film having a low dielectric constant on the thin film transistor array substrate and a transparent electrode film on the phase retardation dielectric film, the phase retardation dielectric film compensates phase retardation of light resulting from light with a tilt incident angle passing through liquid crystal between the thin film transistor array substrate and a liquid crystal substrate.