Real-time super-resolution photoacoustic imaging based on speckle illumination and high-speed computed tomography

Photoacoustic imaging has demonstrated remarkable potential for providing both structural and functional information about biological tissue. However, acquiring real-time images with a resolution beyond acoustic resolution limit remains a critical challenge. In this study, we propose a speckle illumination photoacoustic computed tomography (SIPACT) system to overcome this limitation. This system combines high-repetition speckle illumination with rapid data acquisition, enabling real-time imaging. Leveraging multiple speckle-illuminated frames, the reconstruction method, based on the fast iterative shrinkage-thresholding algorithm, produces images with the resolution exceeding the acoustic limit. Numerical simulations and experiments demonstrate that the SIPACT system improves the resolution of photoacoustic image from 78 μm to 44 μm, with acquisition time that takes only 0.1 ∼ 0.2 s. This advancement enables real-time imaging and enhances image quality, which might promise valuable imaging applications in biomedical fields.