Investigating the use of terahertz pulsed time domain reflection imaging for the study of fabric layers of an Egyptian mummy

Abstract

This paper reports the first use of terahertz time domain reflection imaging involving textiles on part of a complete human mummy, still in original wrapping. X-ray technique has been used extensively to investigate anatomical features, since X-ray pass through the wrapping. Terahertz waves, on the other hand, can penetrate into non-metallic materials and its reflection depends on the refractive index of materials at the interface, such as textiles and the air. The mummy of Kharushere (ca. 945-712 B.C.) was examined by using Terahertz time domain reflection imaging in the Egyptian galleries of The Metropolitan Museum of Art. Experimental results suggest that the Terahetz imaging is a promising technique for probing the fabric layers surrounding Egyptian mummies, although it is still very limited in its current state. In the future it could become a useful complement to CT scanning when materials with low radiographic density and contrast are being investigated.

Wideband THz Time Domain Spectroscopy based on Optical Rectification and Electro-Optic Sampling

“…Moreover, the negligible ionization power of the THz radiations compared to optical and X-rays technologies make them perfectly suitable for biological applications6. For the above-mentioned reasons, THz technology are penetrating in lots of areas, beyond fundamental Physics investigation, spanning from medical care and homeland security to cultural heritage conservation78910111213. The most challenging technology development remains in the area of THz sources and detectors, since, in general, both wide band and high power are required at the same time.…”

Terahertz pulse imaging in archaeology

“…They demonstrated that with TPIS it was possible to recognize differences in the desiccated flesh and that it adds a temporal aspect that does not exist in other techniques, despite TPIS having coarser resolution than XRCT. Fukunaga et al also confirmed that THz imaging may complement X-ray images when materials with low radiographic density and contrast are being investigated [3]. From the XRCT images taken on this bird mummy ( Fig.…”

“…In particular with mummies, TPIS has been explored as an alternative -or complement -to X-ray imaging techniques [2,3]. It is the combination of material characterization, time of flight imaging, and the penetration of optically opaque materials that gives rise to applications for subsurface imaging of many culturally significant objects.…”

Terahertz, X-ray and neutron computed tomography of an Eighteenth Dynasty Egyptian sealed pottery

“…In Egyptology, THz imaging has been used for the analysis of an ancient Egyptian mummy [9], written papyrus [10] and clay artifacts [11]. Fukunaga et al [12] reported the first use of THz timedomain reflection imaging for the analysis of textiles of an Egyptian human mummy preserved at the Metropolitan Museum of Art (New York). They pointed out the difficulty of conventional X-rays to visualize the bandages due to the low radiological contrast of the fabric layers.…”