由于太赫兹辐射能量低并且脉冲宽度窄(皮秒量级), 太赫兹时域光谱技术作为一种提取材料光学参数的新兴光谱分析手段具有无损伤和高时间分辨率的特点。法布里-珀罗震荡是透射模式太赫兹时域光谱提取薄片的光学参数的主要障碍。为了即时地滤除法布里-珀罗震荡以获得薄片准确的光学参数提出了一种可靠的方法。该方法为每一片测量样品实时地设计其独有的带阻滤波器以滤除叠加在折射率和吸收系数的初始值中的法布里-珀罗震荡。同时不同掺杂的硅片和氨基酸薄片的实验结果证实了该方法的可行性。

Due to the low THz radiation energy and narrow pulse width(picosecond range), as a new spectral analysis method, terahertz time-domain spectroscopy(THz-TDS) technology is nondestructive and high-temporal-resolution when being used to extract optical parameters of samples. Fabry-Pérot interference is a crucial obstacle in extracting optical parameters of thin wafers in the THz-TDS through-transmission mode. A reliable algorithm was proposed and tested to simultaneously filter Fabry-Pérot interference and obtain precise optical characterization of thin wafers. The algorithm employs a band-stop filter immediately and exclusively designed for every single sample to the initial refractive index and absorption coefficient. Experimental results of doped silicon wafers and amino acid tablets confirming the utility of the algorithm were also presented.