激光波长合束精度研究

Laser beam combination accuracy of wavelength multiplexing

对双光束波长合束精度进行了研究。用镀有特制光学薄膜的滤光片对波长为532和515 nm的两束激光进行合束,并对合束精度进行检测。基于此系统,建立了对应理论模型,并对合束及检测的误差来源和大小进行全面分析。两光束指向稳定性均为50μrad时,合束精度理论值为14.69″,指向稳定性所占比例为99.26%,系统对质心定位等不稳定因素(误差变化<3倍)抗性极好,精度变化<2.4‰;指向稳定性提高到23.51μrad时,合束精度理论值为7.09″,指向稳定性所占比例为96.77%,系统仍有较高抗干扰能力,精度变化<1%。分析表明,影响近场小功率合束精度的因素有激光指向稳定性、机械调节和质心定位误差,其中激光指向稳定性是主要因素。通过调节各因素的比例,可对合束的抗干扰能力进行控制。

Double laser beam combination accuracy of wavelength multiplexing is carried in this article .Two beams with wavelengths of 532 nm and 515 nm are combined into one in the combination and detection system using light filter with special optical thin films , and the combination accuracy is detected .Based on this sys-tem, the corresponding theoretical model is established , and the comprehensive analysis on the error source and the value in combination and detection are given in this paper .When the pointing stability of both beams is 50 μrad, the theoretical value of combination accuracy is 14.69″, and the proportion of pointing stability is 99.26%.The system gets an excellent anti interference ability against the unstable factor such as the error of centroid location（error rate〈3 times）, and the variation in accuracy rate is less than 2.4‰.When the laser pointing stability is increased to 23.51 μrad, the highest theoretical value of combination accuracy is 7.09″ and the proportion of pointing stability is 96.77%.The system still has a high ability of anti-interference and the variation in the accuracy rate is less than 1%.Factors that affect the beam combination accuracy of near field and small power are laser beam pointing stability , mechanical adjustment and centroid location error are all the factors to affect the combination accuracy of the near field beam with low power , among which the laser pointing stability is the main factor .Adjusting the proportion of each factor , we can control the ability of anti interference of beam combination .