矩阵法研究拼接光栅的远场特性

光栅在许多应用场合中需要有较大的尺寸.光栅拼接技术是目前国内外广泛采用的解决光栅尺寸的技术途径之一.拼接光栅尺寸大,能负载的能量也比普通的有限口径光栅压缩器的大N×M倍,但同时引入了波前畸变,从而影响聚焦光束的时间、空间特性.利用矢量法分析拼接子光栅在存在调节偏差的情况下的远场分布特性,结果表明,任何偏差最终对焦斑的影响在空间域上都与位移偏差的作用等效,偏差量应根据应用控制在一定精度范围内,并给定实验参数,模拟计算了相应的各维偏差的设计精度,为拼接系统的检测提供了理论依据.

An analysis of focal spot characteristic of tiling-gratings with matrix method

Tiling-grating is one of the important ways widely used to solve the limited size of grating. Tiling-gratings could he N × M times larger than traditional gratings, nevertheless, introduce wave-front distortion, which impacts the spatial and time characteristics of focal beams. The variation of fo-ca]spot was simulated by using matrix method and the results showed that any alignment errors could be equivalent to piston errors in the spatial domain and it must be controlled within an error range accordingly. Based on the experimental parameters, designing precision was simulated systematical-ly. This work presents important theoretical basis for the testing of a tiling-grating system.