Terahertz Wavelength Measurement Using Metal Mesh Fabry-Perot Interferometer

THz wave refers to the frequency from0.1to10THz (1THz=1012Hz), the electromagnetic radiation between the microwave and optical frequency band. Because the terahertz wave locates in the special position, it has the very important academic research and application value, such as for most material high penetrability, and the rich spectrum characteristics of material in THz frequency, so it has wide and important applications in biomedical, safety inspection, spectrum and imaging technology.In this thesis, it layout a kind of simple structure, easy to adjust, measuring fast, high precision of measurement method of figuring up the wavelength of terahertz. The metal mesh making up Fabry-Perot interferometer (Fabry-Perot Interferometer, hereinafter referred to as the FPI), when terahertz radiation in vertical FPI incident, beam in two metal mesh happened interference. In the measurement, make one of the mesh fixed, another mesh fixed in displacement on the platform, by moving the displacement platform to change the distance between the two mesh. Such detection receiver will appear periodically strong light peak, which can calculate the wavelength of the terahertz wave. By comparison, the experimental results of calculation method of terahertz wavelength using the FPI method and energy conservation the calculated value of the agreement is very good allowed within the scope of in error. This paper main work is in the following aspects:Using the micro nano electronic manufacturing process making a number of different period of metal grid samples. Simulation design samples parameters and manufacture the samples, and use of terahertz Time Domain Spectrum (TDS) system to measure sample and analysis optical properties.Building terahertz sources TPO experiment device using lithium niobate crystal parameters of the vibration method, realizing the terahertz radiation. Using Quantel Ultra1064nm pump laser and TPO device through the Angle of different frequency tuning realize Terahertz output.Set up computing wavelength of terahertz system based on FPI. Manual scans measured transmissivity of terahertz wave of the different space of the FPI, fitting the experimental data to get terahertz wavelength, compared the calculated result to the theoretical calculation result, the results show that the method is accurate and feasible.