摘要
传统的光束漂移量测量系统利用近、远场测量设备分别测量光束的平漂量和角漂量,结构复杂、实时性低。散焦光栅焦平面处正、负一级衍射斑的位置变化可同时反映光束的平漂量和角漂量,为验证该理论、搭建简化的测量系统需要对光路设计进行仿真。基于散焦光栅的成像机理,利用Matlab软件构建了光束通过散焦光栅的成像模型,仿真结果与理论分析一致;最后对光栅和透镜等不同光路设计参数与最大漂移量测量幅值的关系进行了模拟。结果表明,在成像单元约1cm2、短焦透镜焦距约12cm的条件下,为实现漂移量测量精度和可测幅度的最大化,散焦光栅需要离轴15mm,散焦光栅与短焦透镜的焦距比为6。
Tradition systems of beam drift measurement always need measuring at near field and far field respectively, so they are complex and non-real time. A new theory of drift measure- ment based on the location change of diffraction spot was proposed, which was not applied. For verifying the theory and building a predigested measurement system, the design of the key elements needed to be simulated. Based on the imaging theory of defocus grating, the model of beam transmission was built by Matlab. The simulation result was consistent with the theory. Finally, the relation between the key parameters of the grating and the maximum drift value was simulated and analyzed. The Results shows that the best design parameters can be ob- tained while the off-axis value of defocus grating is 15 mm and the focus length ratio of defocus grating to short focus lens is 6 under the condition of the imaging unit 1 cm2 and the focus of short lens 12 cm.
出处
《应用光学》
CAS
CSCD
北大核心
2013年第2期313-318,共6页
Journal of Applied Optics
关键词
散焦光栅
光束漂移测量
仿真分析
defocus grating
beam drift measurement
simulation and analysis