量子级联激光器具有体积小、重量轻、电光转换效率高及可直接调制等特点, 目前逐渐在诸多领域开展应用。单管量子级联激光器输出激光近似为高斯光束, 利用高斯光束传输规律, 理论分析了激光光束质量的评价方法。实验测量了单管量子级联激光器的输出激光近场和远场的光斑分布, 计算了输出激光发散角, 并利用M2因子评价了输出激光光束质量。

Quantum cascade laser (QCL) has been used in many fields for its characters of small size, small weight, high efficiency and direct modulation. The output laser beam of the QCL is nearly to be Guassian style. The evaluating method of the laser beam quality is analyzed in theory based on the Gaussian beam transmission law. And the output near field and far field of the single quantum cascade laser is measured in the experiment. The output divergence angle is calculated and the output beam quality is analyzed by using the M2 factor.