红外窗口导致的气动光学效应将对高速导弹的红外成像制导产生重要影响, 文中在等离子体射流中对二维尖劈模型中的石英窗口进行加热, 测量了一定射流条件下红外窗口表面温度分布和热流分布; 利用径向剪切干涉技术, 测量了气动加热条件下红外窗口引起的传输光束波面相位的变化, 获得了点扩散函数和斯特列尔比的变化。实验结果表明: 热环境下的红外窗口导致传输光束的远场强度发生衰减, 能量分布发生扩散, 光束的会聚性显著降低。

Aero-optical effect caused by infrared window in aerothermal environment has a serious effect on infrared imaging detector of high-speed missile. Experimental study on this effect which was carried through in plasma wind tunnel was represented in the paper. The surface temperature and heat flux of infrared window were measured in the experiment. Wavefront phase of light through the infrared window was measured with a radial shearing interferometer. The changes of point spread function and Strehl ratio with duration of heat were obtained. It is validated that infrared windows result in intensity attention and energy distribution disperse for light beam in far-field.