飞行时间太赫兹断层成像

Time-of-Flight Terahertz Tomography

介绍了利用超短激光脉冲的高分辨飞行时间太赫兹断层成像的发展。其基本原理是,首先非线性光学晶体获得的宽带太赫兹脉冲进入到样品,随后检测每一层反射回来的回波脉冲。利用高斯窗口的去卷积过程我们可以获得清晰、高分辨的断层成像谱图。与聚四氟乙烯薄膜机械厚度测量的结果比较,如果一个样品的折射率为n,则轴向分辨率低于10/nμm。

This article describes the development of high-resolution time-of-flight terahertz tomography using an ultrashort laser pulse. Broadband terahertz pulses obtained using a nonlinear optical crystal were injected into samples and the echo pulses reflected from each layer were detected. The deconvolution process was then carried out with a Gaussian window to obtain clean,high-resolution tomographic images. For a sample with a refractive index of n,the axial resolution was below 10/n μm,as determined by comparison to the mechanical thickness measurements of PTFE films.