全息拼接光栅的误差研究

为了制作大面积拼接光栅,对全息光栅拼接误差进行了分析。利用参考光栅与光场光栅形成的莫尔条纹来控制拼接光栅位置和误差,确定了参考光栅莫尔条纹间距、倾斜度及相位与拼接光栅位置之间的关系。研究了参考光栅面和拼接光栅基片不平行时莫尔条纹与拼接光栅条纹的相位一致性,计算了光程差漂移对拼接光栅相位对准误差的影响,分析了工作平台移动对光栅拼接误差的影响。得出光栅拼接总误差为0.15λ,该误差接近光栅拼接精度要求,通过实验验证了全息光栅拼接误差分析的正确性。结果表明,利用参考光栅进行全息光栅拼接是可行的。全息拼接光栅的误差分析为制作米量级高精度拼接光栅提供了理论支持。

Error analysis of holographic mosaic gratings

In order to make large scale gratings,errors of holographic mosaic gratings were analyzed. The gratings' phase and rotation were designed by monitoring the Moiré fringes formed on the reference grating. The orientation and period of the Moiré fringes can show the grating's rotation condition, and the phase can express the grating's phase condition. The phase congruence of the Moiré fringes and the mosaic gratings is researched when the planes of reference grating and the mosaic grating's substrate are not parallel. In addition mosaic gratings' phase error brought by the drift of optical path difference was studied. The errors of mosaic gratings caused by the movement of workbench were analyzed. Considering all of the factors, the mosaic gratings' error is about 0.15λ.The value can meet the requirement of mosaic grating which is designed to be used for pulse compressor. Finally the precision of mosaic gratings' error was confirmed by the experiment. The results show that it is feasible to make the holographic mosaic grating by using the reference grating. The research of holographic mosaic gratings' error provides the method for making meter-order gratings.