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The present paper reviews the X-ray grating imaging systems at home and abroad from the aspects of technological characterizations and the newest researching focus. First, not only the imaging principles and the frameworks of the typical X-ray grating imaging system based on Talbot-Lau interferometry method, but also the algorithms of retrieving the signals of attenuation, refraction and small-angle scattering are introduced. Second, the system optimizing methods are discussed, which involves mainly the relaxing the requirement of high positioning resolution and strict circumstances for gratings and designing large field of view with high resolution. Third, two and four-dimensional grating-based X-ray imaging techniques are introduced.

Spatial sampling criteria and fast recognition theory based on single view imaging system are proposed for automatic testing the assembly structures inside products in industry applications. There must be a maximum rotary step for an object within which the least structural size to be tested is ascertained. Rotating the object by the step and imaging it and so on until a 360°turn is completed, an image sequence is obtained that includes the full structural information for recognition. It is verified that objects could be recognized at a single or some limited orientations by analyzing the correlations among the image sequence. The theory is applied to the online automated X-ray vision system. Experiments show that the average identification takes less than 5s with 4.5% of wrong recognition expense.

One photoelectrical test method and system were optimal developed for messuring the optical performances of some scintillation crystals. The theoretical Critical Focal Length of the measurement system is firstly deduced and used in order to make the most of both X-ray photons and the effective area of the scintillation crystal panel. Furthermore, coaxial cable ordered is used to replace the carried wire to weaken power noise. Finally, a low-pass filter with 35Hz upper limit cut-off frequency is designed to reduce spike interference of high-frequency noise. Experiments are successfully done to comprehensive test the spectral response, conversion efficiency and spatial resolution of some scintillators, and the results show that the presented system in this paper is helpful to test the scintillator properties.