激光M-Z干涉仪的光功率分配特性与应用

The Optical Power Distribution Characteristics in M-Z Laser Interferometer and its Applications

分析了激光M-Z干涉仪的光功率分配特性,证明了当两相干光束的夹角较小时,M-Z干涉仪的两个输出光场的光功率存在较大差异。两相干光束的夹角越大,单边干涉场光功率越趋于稳定。振幅分光器件由于存在半波损失,使输出两干涉场具有互补对称分布,两个输出光场的光功率之和为恒定值。当采用足够大的相干光束夹角,利用单边干涉场光功率的稳定特性进行差动检测,可以提高应用系统的信噪比。

The optical power distribution characteristics in Mach-Zehnder （M-Z） laser interferometer has been analysed in this paper. It is proved that there is a couple of variant output beam power in the M-Z interferometer when the include angle of two beam is enough small, and when the angle get rise, the single interference field power is more stabilized. Light＇s propagation contains half wave loss which makes the two superposition field symmetrical; the sum of the couple of output beam power is a constant. An application system can get a higher signal to noise rate（SNR） by using differential compensation under an enough large angle of two beam, based on the stabilization properties of interference field power.