摘要
光学影像技术是法庭科学物证检验分析的重要技术手段,具有无损、原位、快速等优势。近年来,随着光学影像技术的不断发展,一些新技术、新方法不断被引入法庭科学领域并付诸应用。光学相干层析技术(简称OCT技术)是一种光学断层成像技术,具有无损、高分辨、快速、断层成像的特点,特别是其可以无损地得到材料或生物组织内部的结构信息,突破了传统二维成像只能进行物质表面分析的局限,因此可成为一种很有前景的新型法庭科学光学影像技术。本文首先介绍了自主搭建的一套三维OCT成像系统,并着重介绍了基于该系统应用于法庭科学油漆物证检验、胶带指纹显现和毛囊特征分析等方面的研究。结果表明,OCT技术非常适合用于法庭科学物证检验分析,作为其他检验的先导技术手段,获取样品内部信息,提取新型光学特征参数。由于其采用光纤化技术,还有望实现便携化、小型化,在现场勘查中开展相关应用。
Optical imaging technology is important for the detection and examination of physical evidence,and has the advantages of non-destructive,in situ and rapid analysis.In recent years,with the continuous development of optical imaging technology,some new techniques and methods have been introduced into the forensic science and put into application.Optical coherence tomography(OCT)is new in forensics and performs high-resolution,cross-sectional tomographic imaging of the internal microstructure in materials and tissues,and without any damages to the evidence.This paper first introduces a custom-built three-dimensional OCT imaging system,and then presents three novel applications by utilizing this system,including car paint analysis,latent fingerprint visualizing and hair follicle analysis.These results show that OCT technology is very suitable for physical evidence examination because of its characteristics of non-destructive high-resolution subsurface imaging.As a novel technology for forensic investigation,OCT imaging obtains internal structural information and new optical features of samples and extracts.In the future,it is expected to be portable and miniaturized and be applied in crime scene investigation.
引文
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