Laser beam combination accuracy of wavelength multiplexing

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 system,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 is99. 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.