Research Of Quasi Optical Path In MIR Diagnostic System At Fusion Plasma

The development of social is depended by energy. The fossil fuels has brought social and economic development, such as coal, oil, natural gas et al. But as well as the continuous development of human industry, the existing traditional energy has been unable to ensure the rapid and sustained industrial development needs. At the present stage, controlled nuclear fusion is the methods that found to have a greater hope which can solve the energy gap problem to ensure survival and development of the future eventually, the main methods of controlled nuclear fusion is divided into ultrasonic fusion, laser constraints(inertial confinement) fusion, magnetic confinement fusion(Tokamak), while tokamak is a major means of the current development of controlled nuclear fusion. In past studies, the controlled nuclear fusion has made great progress, and development has been a number of important ways to diagnose plasma parameters, such as probes, spectroscopy, mass spectrometry, scattering, microwave measurement, impedance measurement, holographic interference method, etc., can be directly measured by a series of parameters characterizing the plasma characteristics and its distribution.With the deepening understanding of the plasma, found that turbulence is a very important physical quantity in magnetically confined plasma. To measure the turbulence of plasma, microwave reflectance imaging gradually developed to become the ideal means of measurement. In complete microwave reflectance imaging systems, diagnostic techniques and the basic principles of microwave reflectance imaging quasi-optical imaging is its main support. Spatial resolution in microwave imaging system is an important parameter, so for the quasi-light path part, to the number of blocks or by adjusting a quasi-optical lens to change the resolution of the system, enabling the system to adjust the microwave reflectance imaging detect region-wide. Reference optical imaging principle, the aberration is more central parameters in imaging. Therefore, in the quasi-light path, to make the system to meet the imaging point to point by adjusting the imaging lens to achieve good aberration. This paper combines the quasi optical principles and beam propagation characteristics of Gauss, sorting microwave reflector diagnostic technology concepts and methods of diagnosis; carding optical imaging principle, lens and reflector system designed comparative analysis, imaging resulting difference for system analysis; the system used to separate the spectroscope design analysis, testing and processing.The introduction of quasi-optical system in the microwave reflection imaging system, this is the most fundamental difference of microwave reflector system with other diagnostic imaging diagnostic system mentioned in the text. Thus, the quasi-optical system has an important position in the reflected microwave imaging system. The alignment of the optical system design, focusing on the radius of curvature and the radius of the beam spot of the Gaussian beam wave front.In this paper, combining the theoretical basic related to microwave reflection imaging systems, and use of simulation software to simulating, designed to give a theoretical model of the system. Microwave reflection imaging system of design obtained were working on 8mm band and 5mm band, reflector mirror is used to design in imaging optical of 8mm band quasi-optical system, spatial resolution of 3cm~7cm. Reflector mirror is used to design in imaging optical of 5mm band quasi-optical system, spatial resolution of 2cm~5cm. Quasi-optical system is mainly used for spread the Gaussian beam detected information at plasma cut surface to the detect antenna array, to realize the processing of information, the nature of the plasma probe has a certain practical significance.