Research Of Optical Parametric Amplification Crystals Tiling Technology And Its Tiling Errors Compensation

Optical parametric amplification crystal is key optical components in the opticalparametric chirped pulse amplification (OPCPA) system. It is difficult to obtain a singlecrystal of large aperture for BBO and LBO crystals which are commonly used. Themaximum energy output of OPCPA system that use BBO and LBO crystals is more than10J. Comparing with BBO and LBO crystal, YCOB crystal can be obtained largerdiameter, but its aperture can’t meet the requirements. It is very difficult to obtain asingle crystal with superior capabilities such as large effective nonlinear coefficient,high damage threshold, little affected by thermal effects and not easy to deliquescence.Crystals tiling technology is a good way to solve the problem of nonlinear crystalaperture limit in the process of optical parametric chirped pulse amplification. In theend of OPCPA system, using a large diameter optical parametric amplification crystal toamplify seed pulse can increases the output capacity of the amplifier effectively. Inorder to obtain large diameter optical parametric amplification crystal, this paperproposes a crystals tiling method which composed of the adjustment independent andthe error compensation. Base on the method we have done the following works:①Base on the basic theory of optical parametric chirped pulse amplification, acrystals tiling theoretical model is established. Analyze the type of crystals tiling errorsand research the effects on OPCPA process of the errors. Provide a theoretical basis forthe design of crystal tiling frame.②Design a2×2array crystal tiling adjustment structure. Clamping mechanismstructures for crystals are designed and analyzed. Low stress clamping method forcrystals is researched. Crystal tiling adjustment mechanism is designed, and adjustmentprecision of crystals tiling is calculated to ensure each crystal’s adjustment precision tomeet the requirements.③Error compensation method for machining errors of crystals is designed, basicstructure and control principle of the error compensation system is studied. The errorcompensation system’s closed-loop control model is analyzed for PID controlparameters simulation.④The adjustment function of the2×2array crystal tiling adjustment structure isverified by experiment. By using transmissive element instead of crystals to verify thefeasibility and stability of crystal tiling system and get a good results. The experiment shows that the crystals tiling system is feasible.