應用於翡翠分析之多光譜變焦觀察鏡設計

Multispectra Tunable Forensice Lens Design for Jadeite Analysis

羅如謙(Luo, Ru Chian)

指導教授 ： 葉哲良

國立清華大學/工學院/動力機械工程學系/碩士(2015年)

摘要

面對市場上冒充高品質寶石的優化處理寶石與人工寶石，高階鑑定儀器的體積、重量以及高成本使得買家與收藏家在選購寶石時難以利用科學分析與鑑定；另外，傳統檢測儀器則仰賴經驗與操作技巧，未經標準訓練很容易造成誤判。因此，本論文的目標以翡翠分析為例，設計一個應用於翡翠分析之可攜式多光譜觀察鏡，結合本實驗室在介電式液態透鏡的研究與應用，設計一個具備三段放大(5 ~ 10 X)之寶石觀察鏡，透過明暗場照明設計拍攝放大觀察影像，以獲得內部顏色分布、氣泡、裂隙與外部裂隙等表面特徵；另一方面，整合紫外螢光光譜與可見光吸收光譜測量天然翡翠於波長437 nm之吸收特徵與灌膠翡翠於500 nm左右之螢光反應，以及使各顏色翡翠致色之500 ~ 700 nm波長之吸收特徵，以達到真假翡翠、酸洗灌膠翡翠與染色翡翠之分析，並且設計為成本低、體積小之可攜式系統，將來應用在翡翠與相關寶石分析。

關鍵字

翡翠分析 ； 多光譜影像 ； 寶石觀察鏡 ； 液態透鏡

並列摘要

Nowadays, synthetic and treated gemstones are often seen to imitate high quality gemstones in the trading market, causing scams and great loss to consumers. However, identification instruments are usually large, heavy and high cost, in the other hand, using detection tools require experience and operating skills to avoid false results. Therefore, the goal of this research is to design a portable multispectra tunable forensic lens for jadeite analysis. The gemstone tunable forensic lens with three-step (5 ~ 10 X) magnification is based on the research of dielectric liquid lens, which is able to capture internal and surface characteristics such as color distribution, bubble trapping, and cracks by bright field and dark field illumination. Besides, visible and ultraviolet light are used to detect the absorption spectra of natural jadeite (437 nm), implement jadeite (500 nm UV reaction), and jadeite color spectra around 550~700 nm (green jadeite at 630, 660 nm). With the analysis by the low cost, small volume and portable mulitispectra forensic lens, people will be able to receive information of jadeite or other gemstones for preliminary analysis.

並列關鍵字

Jadeite analysis ； Multispectra imaging ； Gemstone forensic lens ； Liquid lens

參考文獻

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[8] “Jade Quality Factors”, Gemological Institute of America.

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