Karagiannis G, Salpistis Chr, Sergiadis G, Chryssoulakis Y
ORMYLIA Art Diagnosis Centre, Sacred Convent of the Annunciation, 63071 Chalkidiki, Greece.
Rev Sci Instrum. 2007 Jun;78(6):065112. doi: 10.1063/1.2744236.
In the present work, a powerful tool for the investigation of paintings is presented. This permits the tuneable multispectral real time imaging between 200 and 5000 nm and the simultaneous multispectral acquisition of spectroscopic data from the same region. We propose the term infrared reflectoscopy for tuneable infrared imaging in paintings (Chryssonlakis and Chassery, The Application of Physicochemical Methods of Analysis and Image Processing Techniques to Painted Works of Art, Erasmus Project ICP-88-006-6, Athens, June, 1989) for a technique that is effective especially when the spectroscopic data acquisition is performed between 800 and 1900 nm. Elements such as underdrawings, old damage that is not visible to the naked eye, later interventions or overpaintings, hidden signatures, nonvisible inscriptions, and authenticity features can thus be detected with the overlying paint layers becoming successively "transparent" due to the deep infrared penetration. The spectroscopic data are collected from each point of the studied area with a 5 nm step through grey level measurement, after adequate infrared reflectance (%R) and curve calibration. The detection limits of the infrared detector as well as the power distribution of the radiation coming out through the micrometer slit assembly of the monochromator in use are also taken into account. Inorganic pigments can thus be identified and their physicochemical properties directly compared to the corresponding infrared images at each wavelength within the optimum region. In order to check its effectiveness, this method was applied on an experimental portable icon of a known stratigraphy.
在本研究中，我们展示了一种用于绘画研究的强大工具。它能够在200至5000纳米之间进行可调谐多光谱实时成像，并同时从同一区域采集多光谱光谱数据。对于在绘画中进行可调谐红外成像的技术（Chryssonlakis和Chassery，《物理化学分析方法和图像处理技术在绘画艺术作品中的应用》，伊拉斯谟项目ICP - 88 - 006 - 6，雅典，1989年6月），我们提出了“红外反射成像”这一术语，该技术在800至1900纳米之间进行光谱数据采集时特别有效。诸如底层绘画、肉眼不可见的旧损伤、后期修补或覆盖层、隐藏签名、不可见铭文以及真伪特征等元素，都可以通过深红外穿透使上层颜料层逐渐变得“透明”而被检测到。在进行充分的红外反射率（%R）和曲线校准后，通过灰度测量以5纳米的步长从研究区域的每个点收集光谱数据。同时也考虑了红外探测器的检测限以及通过所用单色仪的微米狭缝组件射出的辐射的功率分布。由此可以识别无机颜料，并将其物理化学性质与最佳区域内每个波长下的相应红外图像直接进行比较。为了检验其有效性，该方法被应用于一幅已知地层结构的实验性便携式圣像上。
