National Engineering Laboratory for Forensic Science, Institute of Forensic Science, Ministry of Public Security, Beijing, 100038, China.
School of Forensic Science and investigation, People's Public Security University of China, Beijing, 100038, China.
J Forensic Sci. 2020 Nov;65(6):2071-2079. doi: 10.1111/1556-4029.14514. Epub 2020 Jul 20.
Determining the sequence of intersecting lines is a significant issue in the forensic document examination that can reveal the fraud or distinguish between different allegations. Optical coherence tomography (OCT) is a high-resolution cross-sectional imaging technique that has been introduced into forensic science field recently. The potential of OCT as a novel method to determine the sequence of intersecting lines was examined for the first time. In this study, a spectral-domain OCT system with a center wavelength of 900 nm was employed to perform nondestructive examination on determining the sequence of 18 heterogeneous intersecting line samples produced using three types of gel pens and three brands of stamp pad ink seals. Two-dimensional (2D) cross-sectional, and three-dimensional (3D) volumetric images of the intersecting lines were obtained by the OCT system. Several features were noted and analyzed to successfully determine the sequence of all the 18 samples. Blind tests were also conducted to demonstrate the effectiveness of OCT technique. The results illustrate that OCT technology can provide an effective and accurate method for sequencing intersecting lines of gel pen ink and seal ink, which may complement the conventional methods used in the examination of questioned documents.
确定相交线的顺序是法庭文件检验中的一个重要问题，它可以揭示欺诈行为或区分不同的指控。光学相干断层扫描（OCT）是一种最近引入法庭科学领域的高分辨率横截面成像技术。首次研究了 OCT 作为一种确定相交线顺序的新方法的潜力。在这项研究中，使用中心波长为 900nm 的光谱域 OCT 系统对使用三种凝胶笔和三种品牌的印泥印章制作的 18 个不均匀相交线样本进行无损检测，以确定顺序。OCT 系统获得了相交线的二维（2D）横截面和三维（3D）体积图像。注意到并分析了几个特征，以成功确定了所有 18 个样本的顺序。还进行了盲测以证明 OCT 技术的有效性。结果表明，OCT 技术可为凝胶笔墨水和印泥墨水的相交线排序提供有效且准确的方法，这可能补充传统的可疑文件检验方法。
