Abstract Speckle intensity in the detector plane is deduced in the free-space optical system and imaging system based on Van Cittert–Zernike theorem. The speckle intensity images of plane target and conical target are obtained by using the Monte Carlo method and measured experimentally. The results show that when the range extent of target is smaller, the speckle size along the same direction become longer, and the speckle size increase with increasing incident light wavelengths. The speckle size increases and the speckle intensity images of target is closer to the actual object when the aperture scale augments. These findings are useful to access the target information by speckle in laser radar systems.
Fund: Project supported by the National Natural Sciences Foundation of China (Grant No. 61172031) and the Fundamental Research Funds for the Central Universities of China (Grant No. K50511070005).
Multiple scattering and modeling of laser in fog Ji-Yu Xue(薛积禹), Yun-Hua Cao(曹运华), Zhen-Sen Wu(吴振森), Jie Chen(陈杰), Yan-Hui Li(李艳辉), Geng Zhang(张耿), Kai Yang(杨凯), and Ruo-Ting Gao(高若婷). Chin. Phys. B, 2021, 30(6): 064206.
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