Kilgus Jakob, Langer Gregor, Duswald Kristina, Zimmerleiter Robert, Zorin Ivan, Berer Thomas, Brandstetter Markus
Opt Express. 2018 Nov 12;26(23):30644-30654. doi: 10.1364/OE.26.030644.
Chemical mapping was demonstrated with a mid-infrared (MIR) microspectroscopy setup based on a supercontinuum source (SC) emitting in the spectral range from 1.55 to 4.5 µm and a MEMS-based Fabry-Pérot filter spectrometer. Diffraction limited spatial resolution in reflection geometry was achieved. A multilayer film consisting of different polymers and mixtures thereof was measured and results were compared to those gained with a conventional FTIR microscope equipped with a thermal MIR source. Results show that compared to thermal sources, the application of the SC source results in higher signal-to-noise ratios together with better spatial resolution and faster scanning. Furthermore, diffraction limited imaging of red blood cells was demonstrated for the first time in the MIR spectral region in reflection mode. The distinctive characteristics of the MIR spectral region in conjunction with the high brightness, spatial coherence and broadband nature of supercontinuum radiation show the potential for improving infrared microscopy significantly.
利用基于超连续谱源（SC）的中红外（MIR）显微光谱装置进行了化学成像，该超连续谱源在1.55至4.5 µm光谱范围内发射，还配备了基于微机电系统（MEMS）的法布里-珀罗滤光片光谱仪。在反射几何结构中实现了衍射极限空间分辨率。对由不同聚合物及其混合物组成的多层膜进行了测量，并将结果与配备热红外光源的传统傅里叶变换红外（FTIR）显微镜所获得的结果进行了比较。结果表明，与热光源相比，超连续谱源的应用可带来更高的信噪比，同时具有更好的空间分辨率和更快的扫描速度。此外，首次在反射模式下的中红外光谱区域展示了红细胞的衍射极限成像。中红外光谱区域的独特特性，再加上超连续谱辐射的高亮度、空间相干性和宽带特性，显示出显著改进红外显微镜的潜力。
