0.2THz连续波近场扫描成像方法及实验研究

Research on 0.2THz Near-field Continuous-wave Imaging Method and Its Experiment

太赫兹(Terahertz-THz)电磁波是指频率在0.1THz～10THz(波长在30μm～3mm)之间的电磁波,它的独特性质使得它在许多领域具有重要的应用前景。本文简要地综合了THz信号的产生与检测方法以及THz成像技术的发展概况,基于固态电子学和准光学技术研究了一种0.2THz连续波成像方法,利用搭建的成像系统开展了典型目标的成像实验及其图像处理方法的研究。成像结果表明,0.2THz电磁波对泡沫塑料、纸盒、皮革等非极性材料具有较好的穿透能力,系统的成像分辨率优于3mm。本文的研究成果在安检、生物医学成像、无损检测等方面具有广阔的应用前景,也为便携式THz成像系统的实现提供了可能。

Terahertz （THz） wave is referred as the electromagnetic wave in the 0.1THz - 10THz frequency band （the wavelength from 30μm to 3mm）. It has many applications due to its unique properties. In this paper, the generation and detection of THz signals and the development of THz imaging techniques are presented in brief. A 0.2THz continuous-wave imaging method based on solid-state electronics and quasi-optics is studied. Imaging experiments are made on some typical objects by using the imaging system developed and the image processing method is studied. The imaging results show that the 0.2THz electromagnetic wave has a good capability to penetrate the non-polar materials such as foams, paper boxes and leather and the imaging system has a resolution better than 3mm. This research achievement is expected to have wide applications in the fields of security inspection, biomedical imaging and non-destructive detection and make the development of a portable THz imaging system possible.