光计算方法实验研究及其在高速OCT成像中的应用

In the age of big data, high-speed processing of big data stream in spectroscopy is in urgent need. However, the high-speed processing of big spectral data stream is hard due to the limited speed of conventional computing tools. In comparison with electronic computing, optical computing does not require photoelectric conversion and therefore has many advantages, such as high speed, low noise and low energy consumption.. We aim to develop the optical computing method to solve the speed bottleneck in spectral data processing using conventional methods. According to the propagation properties of light in dispersive medium and other elements, we aim to design an optical computing system with the customizable impulse response function (IRF) and develop its theoretical model. The optical computing system could implement an operation optically by setting the IRF of the operation as its IRF. Then we aim to obtain the IRFs of different kinds of operations mathematically and perform these operations using optical computing at the world leading processing rate of 10MHz. Finally, we aim to apply the optical computing system to real-time dispersion compensation of high-speed optical coherence tomography (OCT). The novel optical computing OCT could reach a far higher speed than conventional OCT. Furthermore, its resolution will reach theoretical limit resolution and be twice as high as the conventional optical computing OCT, due to dispersion compensation by optical computing. Our research provides a new method and idea for high-speed spectral data processing in biological and medical applications and therefore has both scientific values and wide applications.

在大数据时代，如何实现光谱大数据流的高速处理已经成为亟待解决的问题。然而现有电子计算工具速度有限，难以满足需求。相比电子计算，光计算无需光电转换，因而具有高速、低噪、低能耗等优势。. 本项目拟采用光计算方法解决传统方法在光谱数据处理速度上的瓶颈问题。根据光在色散介质等元件中的传播特性，设计一种可灵活选取冲激响应函数的光计算系统并建立其理论模型。这种光计算系统只需选取特定运算的冲激响应函数，即可实现该运算。随后，推导常用数学运算的冲激响应函数，并在实验中用光计算实现这些运算，达到千万次/秒的国际领先速度。作为应用实例，将光计算用于高速光学相干层析成像（OCT）的实时色散矫正。新型光计算OCT不但速度显著超越使用电子计算的OCT，且由于排除色散影响，分辨能力将提高至此前的2倍，获得理论极限分辨率。光计算为生物、医学等领域中光谱数据流的高速处理提供了新的方法和思路，具有重要科学意义和应用前景。

本项目旨在使用光计算方法解决传统方法在光谱数据处理速度上的瓶颈问题，并将光计算应用于光谱相关的实际问题当中。根据光在色散介质等元件中的传播特性，我们设计了一种可灵活选取冲激响应函数的光计算系统并建立了其理论模型。这种光计算系统只需选取特定运算的冲激响应函数，即可针对光谱实现该运算。随后，我们推导了常用数学运算的冲激响应函数，并在实验中用光计算实现了这些运算，达到千万次/秒的超高速度。数据运算方式包括：整数阶/分数阶微分、积分、希尔伯特变换以及滤波。而且，我们还将光计算用于高速光学相干层析成像的实时色散矫正。在使其成像分辨率达到系统理论极限的同时，实现千万次/秒的线扫描速度。此外，我们还提出了基于光计算系统的高速光谱测量方法，并获得了1兆赫兹的光谱测量速度。相比电子计算，光计算无需光电转换和集成电路，因而具有高速、低噪、低能耗等优势。所以，光计算为生物、医学等领域中光谱数据流的高速处理提供了新的方法和思路，具有重要科学意义和应用前景。