Terahertz Tag Identifiable through Shielding Material

In this study, a terahertz tag identifiable through a shielding material was developed. We propose a tag that employs a color-coded system, which is comprised of several plates of varying thickness placed two-dimensionally, wherein their thickness and location provide identification information. We also made a less expensive tag that uses polyethylene (PE) sprayed with a metal on both sides and made a tag based on saccharide. Furthermore, we compared three machine-learning methods (support vector machine [SVM], K-nearest neighbor [KNN], and principal component analysis [PCA]-SVM) to improve the precision of identification.