Recently, ${\ell }_1$-norm based reconstruction approaches have been used with linear array systems to improve photoacoustic resolution and demonstrate undersampled imaging when there is sufficient sparsity in some domain. However, such approaches have yet to beat the half-wavelength resolution limit. In this paper, the ability to beat the half-wavelength diffraction limit is demonstrated using a 5 MHz ring array photoacoustic tomography system and ${\ell }_1$-norm based reconstruction approaches. We used the array system to image wire targets at $\approx 2-3\mathrm{cm}$ depth in both intralipid scattering solution and water. The minimum observable separation was estimated as $70\pm 10\mu \mathrm{m}$, improving on the half-wavelength resolution limit of $145\mu \mathrm{m}$. This improvement was demonstrated even when using a random projection transform to reduce data by $99\%$, enabling substantially faster reconstruction times. This is the first photoacoustic tomography approach capable of beating the half-wavelength resolution limit with a single laser shot.

最近， ${\ell }_{\mathrm{1个}}$基于线性的重构方法已与线性阵列系统一起使用，以提高光声分辨率，并在某些域中有足够的稀疏性时演示欠采样成像。但是，这种方法尚未超过半波长分辨率极限。在本文中，使用5 MHz环形阵列光声层析成像系统演示了克服半波长衍射极限的能力，并且${\ell }_{\mathrm{1个}}$基于规范的重建方法。我们使用阵列系统在$\approx \mathrm{2个}-3\mathrm{厘米}$脂质内散射溶液和水的深度。最小可观察到的间隔估计为$70\pm 10\mu \mathrm{米}$，提高了半波长分辨率的极限 $145\mu \mathrm{米}$。即使使用随机投影变换来减少数据量，也证明了这种改进。$99％$，大大加快了重建时间。这是第一种能够通过单次激光发射就超过半波长分辨率极限的光声层析成像方法。