Fig. 1. Reflective pseudo-thermal light source. (a) Schematic diagram; (b) coordinate system

Fig. 2. Numerical simulation results of speckle field. (a) Intensity distribution; (b) longitudinal second-order correlation function;(c) transverse second-order correlation function

Fig. 3. Comparison of theoretical and numerical simulation results of normalized intensity fluctuation correlation function

Fig. 4. Theoretical results of longitudinal speckle size lz. (a) Relationship between d and lz under different L; (b) relationship between θp and lz under different θe

Fig. 5. Relationship between θp and lz under different L in X-ray band