为了确定一个KDP晶体支撑系统的合理工作姿态, 研究了工作姿态对支撑系统变形、KDP晶体偏转和激光束入射角的影响。首先, 提出了关键刚度分量的概念, 并采用这一概念对不同工作姿态时支撑系统在重力作用下的变形进行了理论分析。其次, 采用有限元方法计算了重力作用下支撑系统的变形, 以及由此引起KDP晶体的偏转和激光束入射角的变化。最后, 对不同工作姿态时支撑系统的变形、KDP晶体的偏转和激光束入射角的变化进行比较, 并分析了关键刚度分量的影响。数值计算结果表明, 受关键刚度分量的影响, 不同工作姿态下支撑系统的变形、引起KDP晶体的偏转和激光束入射角的变化不同。支撑系统为最优工作姿态时, 激光束入射角的变化达到最小值76 μrad。这一结果满足KDP晶体支撑系工作姿态确定的相关要求。

With the aim to investigate optimum operating postures of the supporting system of a KDP crystal, the influence of operating posture on the gravity-induced distortion of the supporting system, as well as the deflection of the KDP crystal and the incident angle change of the laser beam due to the distortion were studied. A concept of key stiffness component was proposed to theoretically analyze the gravity-induced distortion of the supporting system on the occasion of various operating postures. Using the finite element method, the gravity-induced distortions of the supporting system with different operating postures, the induced deflection of the KDP crystal and the incident angle change of the laser beam were calculated and then compared, thus the influence of the key stiffness components were figured out. The numerical results show that under the function of the key stiffness components, the distortion of the supporting system, the deflection of the KDP crystal and the induced incident angle change vary with the operating postures, and the minimum incident angle change is 76 μrad when the supporting system operates under the optimum operating posture. Hence, the optimum result meets the requirement for ascertainment of the operating posture of KDP crystal supporting systems.