Abstract Contemporary art is particularly delicate as the synthetic materials used for their realization are of poorer quality and durability than the traditional materials. It follows that the contemporary artworks often require imminent restorations as well as in-depth analytical studies of the constituting materials. The non-invasiveness of the scientific methods is a key issue in the diagnostics of contemporary art because it minimizes the need of sampling. In this respect, the potential of Optical Coherence Tomography (OCT) imaging to probe the internal structure of the commercial acrylic paint layers, as a function of their thickness, was investigated and compared with that of the near infrared (NIR) reflectography. In support of these measurements, micro-profilometry, an interferometric technique with micrometric depth resolution, was used to measure the paint layer thicknesses. We show that for some painted materials there is a limited possibility to visualize the underdrawings, when investigated by both OCT and NIR reflectography. This is owed to either the absorption of the illumination wavelength by the paint layer (Cobalt-based paints) or the multiple photon scattering effect (presence of TiO2).

中文翻译：

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通过光学相干断层扫描和红外反射成像探测现代丙烯酸涂料

摘要 当代艺术尤其精致，因为用于实现它们的合成材料比传统材料质量和耐用性较差。因此，当代艺术作品往往需要迫在眉睫的修复以及对构成材料的深入分析研究。科学方法的非侵入性是当代艺术诊断的关键问题，因为它最大限度地减少了采样的需要。在这方面，研究了光学相干断层扫描 (OCT) 成像探测商用丙烯酸涂料层内部结构的潜力，作为其厚度的函数，并与近红外 (NIR) 反射成像进行了比较。为了支持这些测量，微轮廓测量法是一种具有微米深度分辨率的干涉测量技术，用于测量漆层厚度。我们表明，当通过 OCT 和 NIR 反射术进行调查时，对于某些涂漆材料，可视化底图的可能性有限。这是由于涂料层（钴基涂料）或多光子散射效应（二氧化钛的存在）对照明波长的吸收。