The super-resolution near-field optical imaging is an advanced project in the front of high engi-neering science and is an industry that should be developed early in the 21th century in China. In this paper, the historical events and PSTM developments in China are introduced. The imaging expressions of all kinds of the super-resolution near-field optical imaging systems are derived and compared with each others. In general, only with the mode of constant separation of tip-sample may obtain the pure optical image of sample, such as the image of refractive index, reflectivity or transmisivity of sample. The evanescent wave emitted from sample surface and the probe tip smaller than the diffraction limit are the two basic conditions of super-resolution in optical imaging. The other key to obtain the super-resolution is the modulated tip with vertical vibration in the mixture field of evanescent wave and propagating wave in near-field. For the transparent sample PSTM is the best to separate the pure optical image and topography of sampe. The author has applied for two invented patents on PSTM, which will be benificial to the development of PSTM industry in China.