Osnabrugge Gerwin, Amitonova Lyubov V, Vellekoop Ivo M
Opt Express. 2019 Apr 15;27(8):11673-11688. doi: 10.1364/OE.27.011673.
Scattering prevents light from being focused in turbid media. The effect of scattering can be negated through wavefront shaping techniques when a localized form of feedback is available. Even in the absence of such a localized reporter, wavefront shaping can blindly form a single diffraction-limited focus when the feedback response is nonlinear. We developed and experimentally validated a model that accurately describes the statistics of this blind focusing process. We show that maximizing the nonlinear feedback signal only results in the formation of a focus when a limited number of reporters are contributing to the signal. Using our model, we can calculate the minimal requirements for the number of controlled spatial light modulator segments and the order of nonlinearity to blindly focus light through strongly scattering media.
散射会阻止光在混浊介质中聚焦。当存在局部形式的反馈时，散射效应可以通过波前整形技术消除。即使没有这种局部报告器，当反馈响应是非线性时，波前整形也可以盲目地形成单个衍射极限焦点。我们开发并通过实验验证了一个准确描述这种盲目聚焦过程统计特性的模型。我们表明，只有当有限数量的报告器对信号有贡献时，最大化非线性反馈信号才会导致焦点的形成。使用我们的模型，我们可以计算出通过强散射介质盲目聚焦光所需的受控空间光调制器段数的最小要求以及非线性的阶数。
