Lewis E N, Treado P J, Reeder R C, Story G M, Dowrey A E, Marcott C, Levin I W
Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Anal Chem. 1995 Oct 1;67(19):3377-81. doi: 10.1021/ac00115a003.
A powerful new mid-infrared spectroscopic chemical imaging technique combining step-scan Fourier transform Michelson interferometry with indium antimonide focal-plane array (FPA) image detection is described. The coupling of an infrared focal-plane array detector to an interferometer provides an instrumental multiplex/multichannel advantage. Specifically, the multiple detector elements enable spectra at all pixels to be collected simultaneously, while the interferometer portion of the system allows all the spectral frequencies to be measured concurrently. With this method of mid-infrared spectroscopic imaging, the fidelity of the generated spectral images is limited only by the number of pixels on the FPA detector, and only several seconds of starting time is required for spectral image acquisition. This novel, high-definition technique represents the future of infrared chemical imaging analysis, a new discipline within the chemical and material sciences, which combines the capability of spectroscopy for molecular analysis with the power of visualization. In particular, chemical imaging is broadly applicable for noninvasive, molecular characterization of heterogeneous materials, since all solid-state materials exhibit chemical nonuniformity that exists either by design or by development during the course of material preparation or fabrication. Imaging, employing Raman and infrared spectroscopy, allows the precise characterization of the chemical composition, domain structure, and chemical architecture of a variety of substances. This information is often crucial to a wide range of activities, extending from the fabrication of new materials to a basic understanding of biological samples. In this study, step-scan imaging principles, instrument design details, and infrared chemical imaging results are presented. Since the prospect of performing high-resolution and high-definition mid-infrared chemical imaging very rapidly has been achieved with the step-scan approach, the implications for the chemical analysis of materials are many and varied.
本文描述了一种强大的新型中红外光谱化学成像技术，该技术将步进扫描傅里叶变换迈克尔逊干涉测量法与锑化铟焦平面阵列（FPA）图像检测相结合。红外焦平面阵列探测器与干涉仪的耦合提供了仪器复用/多通道优势。具体而言，多个探测器元件能够同时采集所有像素处的光谱，而系统的干涉仪部分则允许同时测量所有光谱频率。采用这种中红外光谱成像方法，生成的光谱图像的保真度仅受FPA探测器上像素数量的限制，并且光谱图像采集仅需几秒钟的启动时间。这种新颖的高清技术代表了红外化学成像分析的未来，红外化学成像分析是化学和材料科学领域的一门新学科，它将光谱学用于分子分析的能力与可视化能力相结合。特别是，化学成像广泛适用于对异质材料进行非侵入性分子表征，因为所有固态材料在材料制备或制造过程中都会因设计或发展而呈现化学不均匀性。利用拉曼光谱和红外光谱进行成像，可以精确表征各种物质的化学成分、畴结构和化学结构。这些信息对于从新材料制造到生物样品基本理解的广泛活动通常至关重要。在本研究中，介绍了步进扫描成像原理、仪器设计细节和红外化学成像结果。由于采用步进扫描方法已经实现了非常快速地进行高分辨率和高清中红外化学成像的前景，因此对材料化学分析的影响是多方面的。
