Single Pulse Process Plasma Electrode Pockels Cell Electro-optical Switch

Gaseous discharging plasma, with very low impedance, has a capability to form transparent charge sheaths rapidly on the surface of a dielectric. Therefore, it can serve as electrode for Pockel's cell electro-optical switch. Contrasted with external ring electrodes, plasma electrodes make more uniform electric field distribution in the crystal, so that electro-optical switch can be scaled arbitrary apertures and shapes. Plasma electrodes Pockel's cell (PEPC) electro-optical switch can effectively resolve lasers control and reverse lasers isolate in inertial-confinement-fusion (ICF) driver systems.Switching speed and uniformity are important parameters of PEPC electro-optical switch. The switching speed is dependent on the time that electrons go through gas-filled cells, and uniformity dependence on plasma distribution of discharging space. The microcosmic physical process of gaseous discharge in PEPC is very complicated, and microcosmic parameters, which influence on performance of electro-optical switch can't directly be obtained by experiments. Therefore, in order to optimize PEPC electro-optical switch characteristics, it is important to establish a physical model to simulate discharge process. The main contents and innovations in this thesis are as following:Firstly, static electric field characteristics of different apertures and shapes of PEPC are simulated. On the cross section light pass, equipotential curves of circular aperture of Pockel's cell are concentric circularity, and equipotential curves of square aperture of Pockel's cell are sparseness on diagonal area. Distribution of equipotential curves can roughly explain the phenomena of crossed intersectional darkness area in the discharge CCD photo of square aperture of PEPC,Secondly, a model of PEPC electro-optic switch driven by one-pulse process is proposed based on its physical mechanism. The relationship between the microcosmic physical processes of gaseous discharge plasma and macrocosmic parameters of PEPC electro-optic switch is analysed. The model is very useful to design excellent electro-optic switch with a large aperture.Finally, influence of operating pressure on the characteristics of PEPC electro-optic...