| A serious factor, which influences on limiting energy characteristics of the modem large laser facilities for realizing Inertial Confinement Fusion (ICF), is an appearance of destructive effects in the frequency conversion crystals of large aperture placed in to the beams. At the case of excess of nonlinear effects appearance threshold, not only are quality reduction of the wave front passing optical elements and energy losses possible, but also the fatal destruction of optical elements in themselves are the most grievous. The Transverse Stimulated Raman Scattering (TSRS) is the most probable destructive nonlinear effects in arranges of the above-mentioned classes. Therefore, motivated by the establishment of prototype (TIL) of SG-HI laser facility of China which will act as ICF driver and integrated with the fund requires of CAEP (China Academic of Engineering physics), TSRS in frequency conversion crystals were studied and the security of crystals was considered according to the require that the ICF driver is one for consumer. This thesis was divided into eight chapters, and the main results and innovations obtained here can be summarized as follows:(1) The physics model of TSRS in frequency conversion crystals has been built up firstly.Based on quantum-mechanical viewpoints and the following physical processes and parameters: the two-photo interaction of light with matter, paraxial diffraction of stokes, Langevin noise sources, reflection at the faces and the edges of crystals, gain coefficient, beam aperture, pulse width and fluence of 3, the physics model of TSRS in KDP and KDP crystals acting as high- fluence frequency convector and the paraxial operator Maxwell-Bloch-Langevin equations have been built up.(2) The calculation programming of TSRS has been written and verified.Based on physics model of TSRS in frequency convector crystals, the calculation programming of TSRS has been written. To prove whether the calculation programming of this article is correct or not, the correlative parameters of LLNL in American have been used in this article. The calculation shows the results of LLNL and this article were consistent in the case of the same input parameters. At the same time, the two calculation results have been compared synthetically and particularity, therefore the calculation programming and method of this article have been proved correct and reliable.(3) The TSRS in frequency convector crystals of ICF lasers have been studied for the first time.The KDP or KDP crystals was chose as frequency conversion crystals commonly and the cost of KDP crystals was higher than KDP crystals. At one time, the(peak Stokes fluence) in the two types of crystal was different. It was decided by which crystals can endure the damage of Stokes and the ratio between performance and price to choose which crystals as frequency convectors. According to the technology parameters of the prototype (TIL) of SG-III laser facility, TSRS in frequency convector crystals has been studied quantificationally at two cases of long and short pulse. Based on the reliability, stability and the ratio between performance and price when drivers works, theoretical evidences have been supplied to choose which type of crystals as tripling ones.(4) The characteristics of TSRS in frequency convectors on high-fluence radiation have been studied.The characteristics of TSRS have been studied firstly to form the system and general of study. On the radiation range of l-4GW/cm2, the effects of the modulation in intensity, beam aperture, pulse width and intensity of 3 w on TSRS in frequency convector crystals have been analyzed in detail. The interrelated thresholds have been gained by calculating and theoretical evidences have been offered to prevent TSRS from damaging frequency conversion crystals, which will be applied to the engineering design of the laser drivers on high-fluence .(5) The experiment scheme of TSRS in frequency convector crystals has been designed.It's found that the effect of TSRS...
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