Influence of light spatial coherence on speckle imaging through scattering layers

This work investigates the influence of light coherence on speckle imaging through a scattering layer. A focused laser is incident on a rotating ground glass (RGG). By changing the distance from the focus to the RGG, the degree of coherence of partially spatially coherent light can be controlled. Speckle correlation technique with iterative phase-retrieval algorithm and deconvolution method using point spread function are employed, and their results indicate that the lower the spatial coherence of the light, the higher the quality of the reconstructed object. Moreover, similar conclusions are obtained using an LED as light source. The results suggest that the coherence of light source should be carefully examined and selected to achieve high-quality speckle imaging through scattering layers.