光谱学与光谱分析, 2019, 39 (4): 997, 网络出版: 2019-04-11   

空间偏移拉曼光谱技术的发展及应用

Development and Application of Spatially Offset Raman Spectroscopy
作者单位
1 安徽新华学院, 安徽 合肥 230088
2 中国科学院合肥物质科学研究院, 安徽 合肥 230031
3 中国科学院合肥智能机械研究所, 安徽 合肥 230031
4 中国科学院安徽光学精密机械研究所, 安徽 合肥 230031
5 安徽三联学院, 安徽 合肥 230601
摘要
传统拉曼光谱只能探测样品的表层信息, 或者只能穿透透明的表层探测样品内部, 对多层不透明或不透明包装的样品检测则不适用了, 比如搜索隐蔽的爆炸物、 识别有包装的假药、 无损检测骨骼疾病等。 空间偏移拉曼光谱(SORS)技术是一种新型光谱检测技术, 能够非侵入不透明包装或表层直接获得样品内部深层特征信息, 这一技术的出现解决了上述的难题。 首先详细介绍了SORS技术的工作原理: 其根本原理在于光子迁移理论, 其系统激光光源的入射焦点与光谱系统中收集透镜的焦点在待测样品表层空间上偏移一定的距离ΔS。 当激光入射到待测样品表层时, 表层样品被激发或散射出宽带荧光, 其中有一部分散射光将到达样品内部, 样品内部深层处产生的拉曼散射光子相比于样品表层的光子在散射过程中更易于横向迁移, 经多次散射后返回样品表层被光谱仪器接收系统收集。 到达样品内部不同深度ΔH的散射光返回表层后的位置距离激光光源入射点在样品表层上有不同的偏移距离ΔS。 当空间偏移距离ΔS=0时, 激光光源入射点与拉曼光谱收集点重合, 此处激发的光子密度最大, 系统收集到的拉曼光谱信号大部分来自样品表层, 样品深层拉曼信号被淹没; 当空间偏移距离ΔS≠0时, 光谱仪器收集到的拉曼光谱信号中来自表层的信号衰减很快, 来自样品深层的信号衰减较慢, 使得更深层的拉曼散射光子比重变大, 从而实现光谱分离, 再结合多元数据分析方法可以获得样品内部不同深层次的拉曼光谱, 即空间偏移拉曼光谱。 该技术具有很好抑制表层物质拉曼光谱和荧光光谱干扰的能力, 特别适用于隐蔽在不透明包装材料下的物质拉曼光谱的提取, 从而快速、 非侵入地对目标物成分进行鉴定。 其次介绍了SORS技术的特点。 SORS技术是拉曼光谱的衍生技术, 具备拉曼光谱技术的制样简单、 水分干扰小、 样品消耗量小、 灵敏度高等全部优点, 除此之外, 有效抑制荧光、 深层检测、 非侵入无损检测、 远距离检测等特点, 这些特点有效提高了拉曼光谱强度, 降低用户的检测和生产成本以及提高检测人员的人身安全。 同时概述并对比了SORS技术现有的三种工作方式: 标准SORS、 逆SORS和倾斜SORS。 标准SORS技术可进行远距离非接触测量, 逆SORS较之标准SORS具有更高的灵敏度和抗光谱扭曲的潜力, 而且入射的有效光照面和空间偏移距离ΔS是可控的, 避免了样品过热; 倾斜SORS具有较高的检测灵敏度, 而且实验装置容易实现。 然后在大量调研文献的基础上综述了近些年来SORS技术结合其他技术在化工生产、 安检、 生物医学、 考古艺术、 食品安全、 稽查打假以及**安全等多个领域的国内外发展和应用。 最后指出了SORS技术目前存在的问题并展望了该技术未来的发展前景。
Abstract
The traditional Raman spectroscopy can only detect the surface information of the sample, or can only through the transparent surface detect the inner information of the sample, and it has same problems to get information of multilayer opaque sample or opaque packaging sample, such as searching for hidden explosives, identifying fake medicine with opaque package and non-invasive detection of bone disease, etc.. Spatially offset Raman Spectroscopy (SORS) is a new type of spectral detection technique, which can get information from opaque package non-invasively or gain information through surface layer to inner of the sample directly. This technology solves the problems mentioned above. Firstly, this paper introduced the principle of SORS in detail. The fundamental principle lies in the theory of photon migration. Between the focus point of the incident laser light source and the focus point of the collect lens there is a certain spatial distance offset ΔS from surface of the sample. When the laser light incident into the surface of sample, it will be stimulated or scatter broadband fluorescence by the surface of sample. One part of scattered light will reach to the inner of sample, and the photons of Raman scattered light from inner sample is easier to migrate than the photons of the surface of sample. The photons of Raman scattered light are returned to the surface of sample and collected by optical system after multiple scattering. Scattered light from different depths ΔH have different spatial distance offset ΔS after returning to the surface of sample.When the spatial distance offset ΔS is zero, the focus point of the incident laser light and the focus point of the collect lens are coincided where the density of photons is maximum, and the Raman signal collected by optical system are mostly from the surface of sample, and Raman signal of inner sample is submerged. When the spatial distance offset ΔS is not zero, the Raman signal from the surface of sample collected by optical system is attenuated quickly, but Raman signal of inner sample is attenuated more slowly than that from the sample surface, and this makes the proportion of inner sample more larger, so as to realize the Raman spectral separation. Then optical system will show us the Raman spectral from different depths of inner sample with multivariate data analysis method, and this Raman spectral is the Spatially offset Raman Spectroscopy(SORS). SORS has a good ability to suppress the interference of Raman and fluorescence spectra of surface materials, especially for the extraction of Raman spectra from substances under opaque packaging materials, so as to identify the target components quickly and non-invasively. Secondly, the characteristics of SORS technology are introduced. It is the derivative of Raman spectroscopy. Besides it has all the advantages of Raman spectroscopy, such as simple sample making, less water interference, less sample consumption, high sensitivity, etc.. It also has the special advantages of effectively suppressing the fluorescence, deep detection, non-invasive characteristics of nondestructive detecting and remote detection. These special advantages improved the intensity of Raman spectra effectively, reduced the user’s detection and production costs and also improved the personal safety of the inspectors. At the same time, this paper summarized and compared three existing working methods of SORS technology, standard SORS, inverse SORS and tilted SORS. The standard SORS technology can be used in non-contact remote sensing detection, and inverse SORS compared with the standard SORS has higher sensitivity and potential anti spectral distortion, and the incident light face and the effective spatial distance offset ΔS is controllable, and also avoid the sample overheating. Tilted SORS has a higher detection sensitivity of SORS, and the experimental device is easy to achieve. Then, based on a large number of research papers, the development and application of SORS technology combined with other technologies in chemical production, security inspection, biomedicine, archaeology, food safety, inspection and counterfeiting and national defense safety in recent years were reviewed. Finally, the existing problems of SORS technology are pointed out and the future prospects of the technology are also prospected.

朱婷, 刘洋, 吴军, 王恩亮, 薛峰. 空间偏移拉曼光谱技术的发展及应用[J]. 光谱学与光谱分析, 2019, 39(4): 997. ZHU Ting, LIU Yang, WU Jun, WANG En-liang, XUE Feng. Development and Application of Spatially Offset Raman Spectroscopy[J]. Spectroscopy and Spectral Analysis, 2019, 39(4): 997.

本文已被 2 篇论文引用
被引统计数据来源于中国光学期刊网
引用该论文: TXT   |   EndNote

相关论文

加载中...

关于本站 Cookie 的使用提示

中国光学期刊网使用基于 cookie 的技术来更好地为您提供各项服务,点击此处了解我们的隐私策略。 如您需继续使用本网站,请您授权我们使用本地 cookie 来保存部分信息。
全站搜索
您最值得信赖的光电行业旗舰网络服务平台!