The Application of 2nd Derivative in NIR and MIR Micro-Imaging of Two Plastic Materials
MIR/NIR micro-imaging can supply not only the spectra information but also the spacial distribution information, which is superior to the traditional MIR/NIR spectroscopy analysis. The definition of near/min-infrared micro-imaging is one of the important factors which will influence the correctness of imaging result. In this thesis, two kinds of plastic film which were similar to each other in appearance were regarded as the research object, of which the MIR and NIR micro-images were collected. The raw compare correlation images, 2nd derivative compare correlation images, raw chemimap images and 2nd derivative chemimap images of the MIR/NIR micro-images of the two materials were studied respectively. The result indicated that not only can the preprocessing of 2nd derivative enhance the discrimination of the spectra so as to enhance the image feature but also eliminate the nonuniformity of the compare correlation images. Both the MIR and NIR chemimap images will be inverted after the preprocessing of 2nd derivative. This study will, to some extent, provide some reference to the manufacturing process quality inspection and control and rapid discrimination of the safety of agricultural products and food packaging and the imaging methods of MIR/NIR micro-image.
Pengcheng Wang, Liqun Ai, Yungang Li, Xiaoming Sang and Jinglong Bu
D. Wang et al., "The Application of 2nd Derivative in NIR and MIR Micro-Imaging of Two Plastic Materials", Advanced Materials Research, Vols. 295-297, pp. 2607-2614, 2011