We report the results of measuring the complex coupling coefficients in ring He – Ne lasers with a radiation wavelength of 632.8 nm. It is found that in assembling ring resonators from mirrors of the same quality, there is no correlation between the dissipative and conservative backscattering components. The analysis of the measurement results shows that this behaviour is associated with the speckle structure of the backscattered field in the ring resonator. The presence of backscattering (BS) sources with a random phase on the mirrors’ surface leads to a spread in the values of the BS parameters, which is described by the Rayleigh distribution function. Ways to reduce the spread in the values of dissipative and conservative backscattering components in assembling the ring resonators are discussed.

我们报告了在辐射波长为 632.8 nm 的环形 He-Ne 激光器中测量复耦合系数的结果。发现在由相同质量的镜子组装环形谐振器时，耗散和保守反向散射分量之间没有相关性。对测量结果的分析表明，这种行为与环形谐振腔中反向散射场的散斑结构有关。反射镜表面上具有随机相位的反向散射 (BS) 源的存在导致 BS 参数值的扩散，这由瑞利分布函数描述。讨论了在组装环形谐振器时减少耗散和保守后向散射分量值分布的方法。