Research of algorithm to correct direction drifts of laser beam
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摘要: 为了获得稳定的激光光束,需要对其随机漂移进行校正。以光束传递系统中快速反射镜校正脉冲激光器自身指向漂移的过程为例,采用一种基于移动平均值校正原理的算法,对加载地面抖动前后的校正效果进行了仿真模拟。仿真结果显示,该算法可以使指向漂移经过长距离传输后引入的位置偏移显著降低;校正后的移动平均值相对于校正前的有较大降幅,最优处约降至原来的n-1/2(n为一个窗口内的脉冲数);校正后的移动标准偏差值也明显下降。结果表明,该算法的关键在于提出合适的补偿量,具有实用性,可以实现对激光光束指向漂移的闭环实时校正。Abstract: In order to obtain stable laser beam,random deviations of light beams should be corrected.Taking the progress of adjusting direction drifts of pulse laser beam with fast steering mirrors in the beam delivery system as an example,an algorithm based on moving average(MA) correction mechanism was used to simulate the correction outcomes with or without ground jitters.MA and moving standard deviation(MSD) are used to evaluate the correction effects.The results indicate that this algorithm can control the position excursions on the plane of beam delivery system caused by the direction drifts of laser beam effectively,and the MA corrected has a big jump between n~2n pulses,for example,the optimal MA can be reduced to n-1/2 times(n is pulse numbers in a window).At the same time,there is a sudden decline in MSD between n~2n pulses,and soon afterwards,MSD is going to be sticking.Meanwhile,the drifts can be restrained while loading the ground jitters,and the dropping amplitude is bigger than without the ground jitters.The results show that the key of applications lies in construction of the appropriate corrections.What is more,this algorithm which is practical can achieve real-time control of direction drifts.
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Keywords:
- laser technique /
- correction algorithm /
- moving average /
- laser beam /
- direction drift
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[1] ZHANG G X,CHEN G,HE H,et al.The beam-pointing stability for laser output measure by CCD camera[J].Journal of Applied Optics,1998,19(2):15-18(in Chinese).
[1] ZHAO W Q,TAN J B,MA H W,et al.Laser collimation method based on the drift feedback control[J].Acta Optica Sinica,2004,24(3):373-377 (in Chinese).
[2] XIA J T.Automatie collimation controlling technology of photoelectricity detecting system[D].Nanjing:Nanjing University of Information,2008:1-2 (in Chinese).
[3] HUANG Z L.Error detection based on He-Ne laser beam drift[D].Changchun:Changchun Institute of Optics and Fine Mechanics and Physics,Chinese Academy of Sciences,2004:3-5 (in Chinese).
[4] PAN J,VIATELLA J,DAS P P,et al.Performance and reliability of beam delivery unit for advance lithography[J].Proceedings of SPIE,2004,5377:1894-1901.
[5] CYMER Inc.Lithography laser with beam delivery and beam pointing control:US,2004/0022291A[P].2004-02-05.
[6] LUBLIN L,WARKENTIN D,DAS P P,et al.High-performance beam stabilization for next-generation ArF beam delivery systems[J].Proceedings of SPIE,2003,5040:1682-1693.
[7] WEIGL B,SANDSTROM R.Illumination apparatus and method for controlling energy of a laser source:US,2009/0201955A1[P].2009-08-13.
[8] DAS P P,WEBB R K,GLOWANARDL M,et al.Lithography laser with beam delivery and beam pointing control:US,2003/0022291A[P].2003-04-09.
[9] HEINTZE J.Lithographic apparatus,device nanufacturing method,performance measuring method,calibration method and computer program:China,03140753[P].2003 12-17.
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