Abstract: Contrast Sensitivity is one of the most important parts of visual function. Sine wave grating tests with parallel bars of varying width and contrast were broadly used in visual screening, early diagnosis, and therapeutic evaluation.  Contrast Letter Charts, using optotypes instead of gratings,  are much easier for patients to use. Nowadays, Pelli-Robson Charts has become the standard method not only in eye clinic but also in population based eye studies abroad. Mars Charts, based on the Pelli-Robson Charts, is more sensitive and easy to maintain. In addition, Mars Charts also use numbers as optotypes and will have great potential applications in China.   (Int Rev Ophthalmol, 2015, 39：156-160)