Snapshot spectral ghost imaging, which can acquire dynamic spectral imaging information in the field of view, has attracted increasing attention in recent years. Studies have shown that optimizing the fluctuation of light fields is essential for improving the sampling efficiency and reconstruction quality of ghost imaging. However, the optimization of broadband light fields in snapshot spectral ghost imaging is challenging because of the dispersion of the modulation device. In this study, by judiciously introducing a hybrid refraction/diffraction structure into the light-field modulation, snapshot spectral ghost imaging with broadband super-Rayleigh speckles was demonstrated. The simulation and experiment results verified that the contrast of speckles in a broad range of wavelengths was significantly improved, and the imaging system had superior noise immunity.

We propose a color ghost imaging approach where the object is illuminated by three-color non-orthogonal random patterns. The object’s reflection/transmission information is received by only one single-pixel detector, and both the sparsity constraint and non-local self-similarity of the object are utilized in the image reconstruction process. Numerical simulation results demonstrate that the imaging quality can be obviously enhanced by ghost imaging via sparsity constraint and non-local self-similarity (GISCNL), compared with the reconstruction methods where only the object’s sparsity is used. Factors affecting the quality of GISCNL, such as the measurement number and the detection signal-to-noise ratio, are also studied.