大口径拼接压缩光栅波像差研究

Study on wave aberration of large-aperture mosaic compression grating

为了研究大口径拼接压缩光栅的固定像差和随机像差对光学拼接的影响,采用数值模拟的方法,理论分析了参考光栅的衍射光斑特性。在有效判据的基础上,得到了光栅的拼接精度。结果表明,当拼接子光栅的波像差为1.0λ时,其最大拼缝偏差约为0.26个光栅周期,采取人工干预后,最大拼缝偏差增加到0.42个光栅周期。与此同时,最大角度偏差约为0.71μrad,两种特性参量均比无像差时的拼接要求大幅度降低。这一结果对高能量皮秒激光装置的改进有一定的积极意义。

In order to analyze the effects of fixed and random wave aberration on the large-aperture mosaic compression gratings , by numerical simulation , the far-field characteristics for referenced gratings were studied .On the basis of the precise evaluation criterion , the tiling accuracy of the mosaic gratings was obtained .The results showed that the maximum piston error of the tiling precision was about 0.26 grating period when the wave aberration of sub-gratings was 1.0λ.After manual intervention, the maximum piston error was about 0.42 grating period and the maximum tip-tilt error was 0.71μrad approximately, which were both lower than before .The research is benefit for the improvement of high energy picosecond laser device .