Chen Minyu, Yu Lin, Zhang Yixin
J Opt Soc Am A Opt Image Sci Vis. 2017 Nov 1;34(11):2046-2051. doi: 10.1364/JOSAA.34.002046.
The random fluctuation of the refractive index is an important factor that affects the light transmission in a biological tissue. Here we have derived an expression of signal/noise ratio or equivalent intensity of the orbital angular momentum (OAM) mode for the partially coherent modified Bessel-correlated beam in a turbulent biological tissue. Effects of specific parameters of the biological tissue on it have been studied, such as the outer scale of the tissue index inhomogeneities, the fractal dimension of the particle size distribution, temperature fluctuation strength, and the cutoff correlation length. We argue that selecting a small quantum number of OAM modes is an effective means to improve signal transmission quality. We can adjust the propagation distance, the wavelength of the light source, and the diameter of the receiving aperture to obtain the optimum signal detection results. Also, nondiffracting vortex light can increase the communication channel capacity. Our findings will provide an important theoretical basis for the design and research of medical devices.
折射率的随机涨落是影响生物组织中光传输的一个重要因素。在此，我们推导了在湍流生物组织中部分相干修正贝塞尔相关光束的轨道角动量（OAM）模式的信噪比或等效强度的表达式。研究了生物组织的特定参数对其的影响，如组织折射率不均匀性的外尺度、粒径分布的分形维数、温度涨落强度和截止相关长度。我们认为选择较小量子数的OAM模式是提高信号传输质量的有效手段。我们可以调整传播距离、光源波长和接收孔径直径以获得最佳信号检测结果。此外，无衍射涡旋光可以增加通信信道容量。我们的研究结果将为医疗设备的设计和研究提供重要的理论依据。
