Asynchronous dual-Lissajous scanning for shuffle-coded compressive Raman imaging

We present an asynchronous Lissajous scanning strategy that independently controls the excitation and scattering projection paths, enabling shuffle‑coded compressive confocal Raman imaging. This scanning strategy projects scattered photons onto the spectrometer entrance in a randomly interleaved manner without sacrificing scanning speed. In contrast to the step-and-settle scanning used in earlier SIRI implementations, the continuous Lissajous trajectories enable seamless spatial sampling with a substantially reduced dwell time of the focused laser spot at each sampling point, thereby mitigating photobleaching and photodamage. Furthermore, compared to single-Lissajous scanning of laser beam for undersampling-based compressive hyperspectral imaging, the dual-Lissajous approach achieves significantly improved reconstruction fidelity in both spatial and spectral domains. The feasibility of the proposed method is demonstrated through numerical simulations and experimental studies involving microplastics and single yeast cells.