A switchable nematic liquid crystal (LC) polarizer using the total internal reflection is constructed and its performance characterized. The bandwidth of such a LC polarizer covers the entire visible range. The extinction ratio of the p-wave is found to exceed 10(6). Due to the use of low threshold LC mixture, thin LC layer and high pre-tilt angle alignment layer, the saturation voltage of the LC polarizer is greatly reduced. The switching time of the LC polarizer is about 100 ms at room temperature.