一种提高频谱编码成像技术信噪比的方法  

A Method of Improving Signal-to-Noise Ratio in Spectrally Encoded Microscopy

作　　者：廖九零 高万荣[1] 

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094

出　　处：《光学学报》2015年第3期212-217,共6页Acta Optica Sinica

基　　金：国家自然科学基金(61275198;60978069);国防基础科研资助项目

摘　　要：频谱编码成像技术是一种采用衍射光栅把不同波长照明到样品的不同位置处的新型反射式显微成像技术。搭建了一个基于50 k Hz扫频光源的频谱编码显微系统,为解决无后置放大器情况下探测微弱样品光的问题,采用平衡探测的方法进行了成像测试。通过对USAF-1951分辨率板成像测得横向分辨率由13.93μm提高到5.52μm,采用平衡探测的方法使得洋葱样品图像信噪比(SNR)由15.07 d B提高到22.6 d B。研究结果表明,采用平衡探测的方法能够提高图像分辨率和信噪比。对离体猪胃小凹样品进行成像,验证了频谱编码成像技术在生物消化道内成像的可行性,为下一步该方法实现临床应用奠定了理论基础。Spectrally encoded microscopy is a new reflecting microscopic imaging technique in which a diffraction grating is used to illuminate different positions on the sample with different wavelengths. A spectrally encoded microscopic imaging system is built, and it is based on a swept source at a sweeping rate of 50 kHz. In order to detect the weak light backscattered from the sample without a post-amplifier used, balanced detection is employed. The lateral resolution of the device is improved from 13.93 mm to 5.52 mm by imaging a USAF-1951 resolution target.The images of onion cells show that the signal-to-noise ratio（SNR） increases from 15.07 d B to 22.6 d B by balanced detection, demonstrating the capability of the method to improve both of the lateral resolution and SNR of the system. Images of in vitro swine gastric pits are presented to demonstrate tissue imaging capability of the technique.The work is useful for developing corresponding devices for potential clinical applications.

关 键 词：生物光学 成像系统 频谱编码 显微成像 信噪比 

分 类 号：R318.51[医药卫生—生物医学工程]