Ströbl Stephan, Domke Matthias, Rühm Adrian, Sroka Ronald
Research Centre for Microtechnology, FH Vorarlberg, Dornbirn, Vorarlberg, Austria.
Laser Research Laboratory, LIFE Centre, LMU Munich, Bavaria, Germany.
Biomed Opt Express. 2020 Jun 8;11(7):3601-3617. doi: 10.1364/BOE.394494. eCollection 2020 Jul 1.
The influence of inhomogeneities in the emission characteristics of optical fiber diffusers on the light distribution within biological tissue was evaluated by Monte Carlo (MC) simulations and by experiments on optical phantoms. Due to the strong scattering of light within biological tissue, inhomogeneities in the emission profile become blurred within a short light propagation distance, so that the light distribution within the tissue approaches that of a homogeneous diffuser. The degree of feature vanishing in the light distribution is mainly determined by the width of the inhomogeneities. It was shown that the influence of local inhomogeneities on top of a homogeneous light distribution fades away very effectively within 1 mm of tissue depth, which results in a light distribution very close to that for a homogeneously emitting diffuser. Emission profiles composed of multiple narrow peaks distributed over the full diffuser length with a peak-to-peak distance of less than 2 mm result in an almost homogeneous light distribution after approximately 1 mm of tissue depth. While this article is focused on the impact of diffuser inhomogeneities on the light distribution within the tissue, the importance of further investigations on the related thermal effects is also discussed.
通过蒙特卡罗（MC）模拟以及光学仿体实验，评估了光纤漫射器发射特性的不均匀性对生物组织内光分布的影响。由于光在生物组织内的强烈散射，发射轮廓中的不均匀性在较短的光传播距离内就会变得模糊，从而使组织内的光分布接近均匀漫射器的光分布。光分布中特征消失的程度主要由不均匀性的宽度决定。结果表明，均匀光分布之上的局部不均匀性的影响在组织深度1毫米内非常有效地消退，这导致光分布非常接近均匀发射漫射器的光分布。由多个窄峰组成的发射轮廓，这些窄峰分布在整个漫射器长度上，峰间距小于2毫米，在组织深度约1毫米后会导致几乎均匀的光分布。虽然本文重点关注漫射器不均匀性对组织内光分布的影响，但也讨论了对相关热效应进行进一步研究的重要性。
