Seeing Through Walls: Discovering Europe's Hidden Mural Paintings

这项研究计划的目的是使用便携式脉冲太赫兹成像系统将被灰泥和油漆层层遮挡的壁画可视化。与其他用于研究壁画的技术不同，太赫兹辐射能够穿透几毫米的灰泥，仍然可以检测到模糊的图像，同时还可以提供光谱信息，这些信息可以用来识别壁画颜料和覆盖灰泥的阴影，在某些情况下还可以识别年龄。太赫兹辐射是非电离和非破坏性的，绝不会影响正在调查的文物的完整性。揭开被遮盖的画作将对它们休眠的社区具有巨大的文化意义。它们提供了关于主楼的演变和对更广泛社区以及艺术遗产的影响的关键信息。这项工作的输出将是一个多功能的、面向用户的软件包，根据反射辐射的特性、用于绘制图像的颜料的物理特性、覆盖灰泥的物理特性以及壁画的组成层的厚度来生成大量的2D和3D太赫兹图像。将有设施来在图像中的关键边界产生增强的空间分辨率，并校正由不平坦的石膏表面引入的非高斯噪声。结合这些特征，将确定最佳的图像重建方法。该软件将面向非专业太赫兹用户，希望它将成为将该技术与艺术遗产社区整合的关键。该软件的商业方面将被开发。工作将开始使用模拟壁画，并将开发到最终在实际文物上进行测试。巴黎卢浮宫的研究和修复中心将提供对文物的访问，包括卢浮宫收藏的被遮挡的波提切利画作的碎片，以及欧洲各地其他被遮挡的画作的原产地。在这个软件的支持下，将是对从壁画中反射的太赫兹辐射的关键理论描述，以及一种独特的系统识别方法，将被用来解决太赫兹逆问题。这项工作将为太赫兹研究界撰写基本论文，这对于太赫兹成像作为一种通用成像方式的发展至关重要。在某些情况下，这项工作几乎可以直接转移到其他应用领域。

The aim of this research proposal is to visualise wall paintings which have been obscured under layers of plaster and paint using a portable pulsed terahertz imaging system. Unlike other technologies used to study wall paintings, terahertz radiation is able to penetrate millimetres of plaster and still detect the obscured picture, while also providing spectral information which can be used to identify the shade and in some cases the age of the wall painting pigment and the covering plaster. Terahertz radiation is non-ionising and non-destructive and will in no way affect the integrity of the artefact under investigation.Uncovering obscured paintings will be of huge cultural significance to the communities in which they lie dormant. They provide key information about the host building's evolution and influence on the wider community as well as art heritage.An output of this work would be a multifunction, user orientated, software package to generate numerous 2D and 3D terahertz images, based on properties of the reflected radiation, the physical properties of the pigments used to paint the image, the physical properties of the covering plaster, and thickness of the constituent layers of the wall painting. There will be facilities to generate enhanced spatial resolution at key boundaries in the image and to correct for non-Gaussian noise introduced by uneven plaster surfaces. Optimum image reconstruction methodologies will be identified combining these features. This software will be aimed at non-specialist terahertz users and it is hoped it will be key to integrating the technology with the art heritage community. Commercial aspects of the software will be exploited.Work will begin using mock wall paintings and will be developed to culminate in testing on actual artefacts. The Centre for Research and Restoration, The Louvre, Paris will provide access to artefacts including fragments of obscured Botticelli paintings housed at the Louvre and access to other obscured paintings in their place of origin across Europe.Underpinning this software will be key theoretical descriptions of the terahertz radiation as it is reflected from the wall painting and a unique Systems Identification approach which will be taken to solve the terahertz inverse problem. This work will produce fundamental papers for the terahertz research community, essential for the development of terahertz imaging as a generic imaging modality. This work will be, in some cases almost directly, transferable to other application areas.