Laser Scanners for High-Quality 3D and IR Imaging in Cultural Heritage Monitoring and Documentation

Abstract

Digital tools as 3D (three-dimensional) modelling and imaging techniques are having an increasing role in many applicative fields, thanks to some significative features, such as their powerful communicative capacity, versatility of the results and non-invasiveness. These properties are very important in cultural heritage, and modern methodologies provide an efficient means for analyzing deeply and virtually rendering artworks without contact or damage. In this paper, we present two laser scanner prototypes based on the Imaging Topological Radar (ITR) technology developed at the ENEA Research Center of Frascati (RM, Italy) to obtain 3D models and IR images of medium/large targets with the use of laser sources without the need for scaffolding and independently from illumination conditions. The RGB-ITR (Red Green Blue-ITR) scanner employs three wavelengths in the visible range for three-dimensional color digitalization up to 30 m, while the IR-ITR (Infrared-ITR) system allows for layering inspection using one IR source for analyses. The functionalities and operability of the two systems are presented by showing the results of several case studies and laboratory tests.

Symmetrical Patterns of Ainu Heritage and Their Virtual and Physical Prototyping

“…The digital technology called reverse engineering [16] has been extensively used in cultural artifact preservation and prototyping [17][18][19][20][21][22][23][24][25] because it (reverse engineering) helps create digital or geometric models of existing physical objects when these models (digital or geometric models) are unavailable. In most cases, reverse engineering uses scanning (e.g., [19,20] or image processing [18] techniques to extract the shape, topological, and texture information of an existing physical object.…”

“…The reported patterns exhibit symmetry that can be analyzed using some simple geometric entities, namely, segments of intersecting circles ("vesical piscis"), construction based on equilateral triangles and vesical piscis, construction based on hexagons, construction based on "four circles over one," equilateral triangles, isosceles triangles, equilateral triangles, right angle triangles, regular hexagons, regular pentagons, "5-4-3 triangles," construction based on 36 degree isosceles triangles, equilateral triangle grids, regular hexagon grids, squire grids, square and root triangles, construction based on the golden section triangle and diagonal of a rectangle, whirling square rectangles, squares with Brune's startype divisions, and Brune's stars with intersections [2] (pp. [16][17][18][19][20][21][22][23][24]34). In addition, such simple operations as translation, two-fold rotation, reflection, and glide-reflection applied to the abovementioned geometric entities can create patterns that are often seen in the cultural artifacts of the abovementioned civilizations [2].…”

Mid-wave Infrared Reflectography and Thermography for the Study of Ancient Books: A Review

“…To this aim, spectroscopic techniques have been extensively used for the investigation of pigments and inks following examination with analytical imaging (Havermans, Aziz, and Scholten 2003). In this respect it is worth noting that, unlike most analytical methods, imaging techniques do not require any sampling of the artefact (Gavrilov, Maev, and Almond 2014;Ceccarelli et al 2018). Among imaging methods, the most widely used for the study of books are: X-radiography and tomography, ultraviolet (UV) fluorescence (Knox and Easton 2003;Montani et al 2012), infrared (IR) reflectography (Delaney et al 2009) and multispectral and hyperspectral imaging (MSI, HSI) (Tonazzini et al 2019).…”

A Cost-Effective System for Aerial 3D Thermography of Buildings

“…All this naturally leads to 3D thermography that is usually realized by combining 3D geometric data and two-dimensional (2D) thermographic data [ 35 ], and different setups are available according to the different 3D geometric acquisition systems and the different data fusion. Thus, for example, 3D geometry and 2D thermal images can be simply compared [ 36 ], infrared images can be mapped to 3D point clouds [ 37 , 38 ], integrated at different times in a Building Information Model (BIM) [ 39 ] or associated with a high-quality color laser scanner for cultural heritage monitoring and documentation [ 40 ].…”