相干组束光纤激光干涉图样分布研究

Interference fringes of coherent combining fiber lasers

为了研究两相干组束光纤激光的干涉图样的分布特征,采用数值计算和实验相结合的方法,对干涉图样进行了理论分析和实验验证,取得了在不同光束间距及不同傅里叶透镜焦距下的干涉图样分布图。干涉图样的条纹分布和条纹可见度主要受到激光光束间距、傅里叶变换透镜焦距以及光束束腰半径等参量的影响。随着光束间距的增大,干涉条纹间距减小,条纹数目增多,条纹可见度减小;傅里叶变换透镜焦距增大时,干涉条纹数目没有明显变化,条纹间距略有增加,条纹可见度增大。这一结果对相关实验工作将有一定帮助。

In order to study the characteristics of the interference patterns of two coherently combined fiber lasers, experimental and numerical computing method was used. Based on the theory and experiments the interferent fringes of coherent combining of fiber lasers were obtained. It is shown that the interference strips are mainly affected by the beam separation, focal length of Fourier transform lens and beam waist, etc. With increasing beam separation, the number of interference fringes increases and the fringe separation and visibility decrease. When the focal length of Fourier transform lens increases the fringe separation and number of fringes do not change obviously, but the visibility increases. This work will be useful for relative experiments.