基于太赫兹时域光谱图像序列的运动检测研究

太赫兹时域光谱（THz-TDS）图像是一种新的图像形式，THz—TDS图像的每个像素点是一个一维时间脉冲信号，该信号承载了像素点位置处目标材料在太赫兹（THz）波段的吸收谱或散射谱：由于THz频段覆盖了许多有机大分子和半导体材料分子振动和转动的频率，可以预计，随着THz技术发展的不断深入，THz—TDS技术乃至THz—TDS图像分析技术将会成为研究这些材料基础问题的重要手段。本文针对THz-TDS图像的特点，提出了一种对在THz-TDS图像序列中的目标微小运动进行检测和估计的方法。该方法通过假设目标材料的局部THz特性保持守恒，导出了目标物的运动方程，并通过引入矢量同质微分概念，给出了该方程的近似求解方法。本文最后给出的实验结果验证了方法的可行性和有效性.

Motion Detection in Terahertz Time-domain Spectroscopy Image Sequences

The terahertz time-domain spectroscopy (THz-TDS) image is a new kind of image form. in which ,each pixcl is actually a temporal response pulse signal of THz reference pulse. A THz-TDS image not only provides the geometric information of a specimen, but also provides its absorption spectral or scatter spectral information contained in the THz waveforms. As oscillation and rotation characteristic frequencies of many organic macromolecules and semiconductor material molecules occupying at the range of THz band, it can be expected that, with the de-velopment of THz technology ,THz-TDS image analysis technique will become an important approach to study those materials' characteristics. In this paper,a method to detect small shift motion in the THz-TDS image sequences is proposed. In the proposed method ,by assuming that the THz response characteristic of one object material would be retained in a spatial local region ,a vector partial differential equation depic-ting movement is established, and a kind of vector homogeneous differential operator is introduced to approximate the solution. Finally, two ex-periments are given ,and results show that the proposed method is feasible and effective.