Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul, 02841, Korea.
Department of Physics, Korea University, Seoul, 02841, Korea.
Nat Commun. 2017 Dec 18;8(1):2157. doi: 10.1038/s41467-017-02117-8.
Thick biological tissues give rise to not only the multiple scattering of incoming light waves, but also the aberrations of remaining signal waves. The challenge for existing optical microscopy methods to overcome both problems simultaneously has limited sub-micron spatial resolution imaging to shallow depths. Here we present an optical coherence imaging method that can identify aberrations of waves incident to and reflected from the samples separately, and eliminate such aberrations even in the presence of multiple light scattering. The proposed method records the time-gated complex-field maps of backscattered waves over various illumination channels, and performs a closed-loop optimization of signal waves for both forward and phase-conjugation processes. We demonstrated the enhancement of the Strehl ratio by more than 500 times, an order of magnitude or more improvement over conventional adaptive optics, and achieved a spatial resolution of 600 nm up to an imaging depth of seven scattering mean free paths.
厚生物组织不仅会引起入射光波的多次散射，还会引起剩余信号波的像差。现有的光学显微镜方法在同时克服这两个问题方面存在挑战，限制了亚微米级空间分辨率成像的深度。在这里，我们提出了一种光学相干成象方法，该方法可以分别识别入射到样品和从样品反射的波的像差，并在存在多次光散射的情况下消除这些像差。该方法记录了各个照明通道中背向散射波的时间门控复场图，并对正向和相位共轭过程中的信号波进行了闭环优化。我们证明了斯特列尔比提高了 500 多倍，比传统自适应光学提高了一个数量级以上，并且在七个散射平均自由程的成像深度内实现了 600nm 的空间分辨率。
