Study On Plasma-Electrode For Electro-Optical Switch

With the development of the solid laser for inertial confinement fusion(ICF), the power and the aperture of the laser become larger and larger, and at the same time more and more large-aperture optical components were placed in the laser system. To isolate the retroreflections from the target and the self-oscillation in multipass amplifier system, the large-aperture electro-optical switch is required. The plasma electrodes pockels cell(PEPC) can satisfy the demand of the laser system for ICF, so it is one of the key components in the next generation large-aperture optical switch in the laser system for ICF. But to manufacture PEPC, the large-aperture uniform plasma electrode should be firstly obtained. In this paper the large-aperture uniform plasma discharge produced by gas discharge was discussed in detail as follows:1. The different high-power laser systems were introduced. The status and function of PEPC in these laser systems were described. And we analyzed the structure of the PEPC, and illustrated the importance and necessity of research on plasma electrode for PEPC.2. Aim at the demand of PEPC on plasma electrodes; we analyzed the basic characters of the plasma, the means producing plasma, the characters of plasma formed by gas discharge, the factor affecting the gas discharge and the process of high voltage pulse discharge et al. And the possibility forming large-aperture uniform plasma by gas discharge was illustrated.3. The metal bar cathode, auto-pre-ionization cathode, button cathode, hollowcathode and magnetron cathode were designed by ourselves. The uniform and delay of the discharges using all kind of cathodes were studied under the different voltage, pressure and the method of pre-ionization et al.4. The results of the experiments were systemically analyzed and discussed. And the optimized conditions of large-aperture uniform discharge were obtained.5. The plasma electrodes were used in PEPC. And the distribution of switching efficiency in full aperture, the switching speed and the synchronizes between the discharge currents in both cavity were measured. The switch characteristic parameters proved that it is feasible to use discharge plasma as electrodes in electro-optics switch.In a word, we have studied the large-aperture uniform plasma formed by gas discharge required for researching on ICF driver. It is the first time in our country to study the large-aperture uniform plasma formed by gas discharge. The discharge plasma were directly used in the large-aperture optical switch for the ICF laser system. The switch parameter satisfied the demand of the laser system. Overseas this technology was kept secret from us. And we secondly mastered this technology in the world following America.