Integrated Imaging and Spectroscopic Analysis of Painted Fresco Surfaces Using Terahertz Time-Domain Technique

Terahertz time-domain (THz-TD) imaging plays an increasingly significant role in the study of solid-state materials by enabling simultaneous extraction spectroscopic composition and surface topography far-infrared region (3–300 cm−1). However, when applied to works art reflection configuration, challenges arise, including weak signal intensity, multiple losses, distortion. This proposes a practical solution overcome these limitations conducts integrated analysis on painted fresco surfaces, allowing for retrieval thicknesses, material distribution, pigment signals. The addresses issue geometrical distortion, which hampers accurate determination THz phase signal. By tackling this challenge, work successfully determines absorption coefficient each point retrieves signatures. Additionally, temporal deconvolution technique is employed separate different layers sample differentiate between outer inner topography. objective demonstrate advantages THz-TD determining results obtained highlight potential investigating art, offering new possibilities routine field cultural heritage preservation.