Significance: Optical microscopy is characterized by the ability to get high resolution, below 1 μm, high contrast, functional and quantitative images. The use of shaped illumination, such as with lightsheet microscopy, has led to greater three-dimensional isotropic resolution with low phototoxicity. However, in most complex samples and tissues, optical imaging is limited by scattering. Many solutions to this issue have been proposed, from using passive approaches such as Bessel beam illumination to active methods incorporating aberration correction, but making fair comparisons between different approaches has proven to be challenging. Aim: We present a phase-encoded Monte Carlo radiation transfer algorithm (φMC) capable of comparing the merits of different illumination strategies or predicting the performance of an individual approach. Approach: We show that φMC is capable of modeling interference phenomena such as Gaussian or Bessel beams and compare the model with experiment. Results: Using this verified model, we show that, for a sample with homogeneously distributed scatterers, there is no inherent advantage to illuminating a sample with a conical wave (Bessel beam) instead of a spherical wave (Gaussian beam), except for maintaining a greater depth of focus. Conclusion: φMC is adaptable to any illumination geometry, sample property, or beam type (such as fractal or layered scatterer distribution) and as such provides a powerful predictive tool for optical imaging in thick samples.

中文翻译：

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厚样品成像，分阶段蒙特卡罗辐射传输算法

意义：光学显微镜的特点是能够获得高分辨率、低于 1 μm、高对比度、功能性和定量的图像。使用成形照明，例如光片显微镜，已导致更大的三维各向同性分辨率和低光毒性。然而，在大多数复杂的样本和组织中，光学成像受到散射的限制。已经针对这个问题提出了许多解决方案，从使用贝塞尔光束照明等被动方法到结合像差校正的主动方法，但在不同方法之间进行公平比较已被证明具有挑战性。目标：我们提出了一种相位编码的蒙特卡罗辐射传输算法（φMC），能够比较不同照明策略的优点或预测单个方法的性能。方法：我们表明 φMC 能够模拟高斯或贝塞尔光束等干扰现象，并将模型与实验进行比较。结果：使用这个经过验证的模型，我们表明，对于具有均匀分布的散射体的样品，用锥形波（贝塞尔光束）代替球面波（高斯光束）照射样品没有固有优势，除了保持更大的焦点深度。结论：φMC 适用于任何照明几何形状、样品属性或光束类型（例如分形或分层散射体分布），因此为厚样品中的光学成像提供了强大的预测工具。对于具有均匀分布的散射体的样品，用锥形波（贝塞尔光束）代替球面波（高斯光束）照射样品没有固有的优势，除了保持更大的焦深。结论：φMC 适用于任何照明几何形状、样品属性或光束类型（例如分形或分层散射体分布），因此为厚样品中的光学成像提供了强大的预测工具。对于具有均匀分布的散射体的样品，用锥形波（贝塞尔光束）代替球面波（高斯光束）照射样品没有固有的优势，除了保持更大的焦深。结论：φMC 适用于任何照明几何形状、样品属性或光束类型（例如分形或分层散射体分布），因此为厚样品中的光学成像提供了强大的预测工具。