应用于玉石结构分析的光学相干层析技术

本文首次尝试将光学相干层析方法的微观结构层析分辨能力应用于检测玉石结构进而分析其质地，阐述了光学相干层析图像中反映的玉石结构特征以及物理解释。实验中利用中心波长1310nm的宽带光源和傅立叶域光学延迟线实现了扫描速度1帧/秒、纵向分辨率15um、成像深度3mm的光学相干层析成像系统，根据翡翠样品在层析成像中的光学散射特性随深度变化梯度和在二维被测切面内的强弱分布，提出了评估翡翠透明度和净度特性的光学方法，同时OCT图像特征亦可直观显示古玉钙化沁色部分的光学特性差异。实验结果验证了OCT检测方法用于区分翡翠透光特性的可行性，显示了OCT成像在辨别古玉钙化沁色特征中的应用潜力。

Imaging and Analyzing Subsurface Morphologies of Jade Objects with Optical Coherence Tomography

Our work focuses on the new application OCT technology in gemstone testing. The main problem in jade research and industry is lack of portable fast measurement equipment for quality evaluation. Concerning the ability of exacting the two-dimensional subsurface structure, OCT imaging has the potential to obtain helpful microstructural characteristics and provide more scientific information for jade identification and research work. An optical coherence tomography (OCT) system applied in jade imaging and measurement has been implemented with scanning speed of 1 frame per second, depth resolution of 15um and penetration depth of 3mm. We demonstrate the experimental results and theoretical analysis of Jade imaging and measurement based on OCT method. From one hand, by processing the two-dimensional tomography data, we have provided two parameters to characterize the optical properties and then evaluate the transparency of jade qualitatively. From the other hand, according to the different optical backscattering properties, OCT imaging can be used to observe and provide some discrimination information on the impregnation and calcification of ancient jade materials. Experimental results show available microstructure information and confirm the feasibility of OCT method in evaluating transmission features and analyzing subsurface morphologies of archaic jades. Corresponding physical interpretation is also present in this paper.