Investigation Of Nondestructive Measurement For Micro-vibration With CW THz

The science and technology of terahertz is a newly emerged research field in nearly two decades. involving not only the electromagnetic, optoelectronics, but also the semiconductor physics, material science,biology as well as the medicine were, terahertz also enjoys a great applying prospect in the areas of physics, informatics, astronomy, environmental science and military affairs. Alone with development of the source and detector of terahertz, the interests of the scientists are arisen gradually in the applying research area. It is used in the research of the characteristics of the spectrum, safety and quality inspection,medical diagnosis and the detection of the chemical and biological. This paper is mainly about the application of the Terahertz radiation in the vibration measurements.This thesis is built around the coherent measures of Terahertz radiation. Firstly, the two fundamental techniques—source and detector are introduced. The introductions of several common radiation sources and detectors are also included in this part. Then the methods and theories of some measurement technique of laser are briefly introduced. The coherent detect programs of the no damage-tiny distance measurement of terahertz which is modeled of the Zero-diversity interference mainly involve two parts: the Michelson interferometer and indirect detection of terahertz. The relevant hardware modules which includes the terahertz source, Pyroelectric detector, terahertz Beam splitter, Ferroelectric material are introduced step by step. The interaction between Ferroelectric material and terahertz has been simulated and calculated. The experimental results and analysis including diffraction, interference of the terahertz, coherent experiments are depicted. At last, the problems may exist in the it and the prospect of this research are mentioned in this paper.