Terahertz Defect Detection in Multi-Layer Materials Using Echo Labeling

Dogus Can Sevdiren; Furkan H. Ilgac; Aydin Sezgin

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arXiv · 2502.04135

Terahertz Defect Detection in Multi-Layer Materials Using Echo Labeling

Dogus Can Sevdiren·Furkan H. Ilgac·Aydin Sezgin

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Abstract

Non-destructive testing is an important technique for detecting defects in multi-layer materials, enabling the evaluation of structural integrity without causing damage on test materials. Terahertz time-domain spectroscopy (THz-TDS) offers unique capabilities for this purpose due to its sensitivity and resolution. Inspired by room geometry estimation methods in acoustic signal processing, this work proposes a novel approach for defect detection in multi-layer composite materials using THz-TDS, enhanced by high-power sources. The proposed method utilizes Euclidean distance matrices to reduce problem complexity compared to state-of-the-art approaches, and effectively distinguishes and maps higher-order reflections from sublayers, enabling precise defect localization in composite materials without artifacts.

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Dogus Can Sevdiren, Furkan H. Ilgac, Aydin Sezgin. 2025-02-06. Terahertz Defect Detection in Multi-Layer Materials Using Echo Labeling. https://arxiv.org/abs/2502.04135

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