Institute of Mechanical Engineering, National Yunlin University of Science and Technology, Douliou, Yunlin County 640, Taiwan.
Sensors (Basel). 2010;10(4):2577-86. doi: 10.3390/s100402577. Epub 2010 Mar 24.
The optical structure of general commercial interferometers, e.g., the Michelson interferometers, is based on a non-common optical path. Such interferometers suffer from environmental effects because of the different phase changes induced in different optical paths and consequently the measurement precision will be significantly influenced by tiny variations of the environmental conditions. Fabry-Perot interferometers, which feature common optical paths, are insensitive to environmental disturbances. That would be advantageous for precision displacement measurements under ordinary environmental conditions. To verify and analyze this influence, displacement measurements with the two types of interferometers, i.e., a self-fabricated Fabry-Perot interferometer and a commercial Michelson interferometer, have been performed and compared under various environmental disturbance scenarios. Under several test conditions, the self-fabricated Fabry-Perot interferometer was obviously less sensitive to environmental disturbances than a commercial Michelson interferometer. Experimental results have shown that induced errors from environmental disturbances in a Fabry-Perot interferometer are one fifth of those in a Michelson interferometer. This has proved that an interferometer with the common optical path structure will be much more independent of environmental disturbances than those with a non-common optical path structure. It would be beneficial for the solution of interferometers utilized for precision displacement measurements in ordinary measurement environments.
通用商用干涉仪（如 Michelson 干涉仪）的光学结构基于非共光路。由于不同光路引起的相位变化不同，这种干涉仪会受到环境影响，因此测量精度会受到环境条件微小变化的显著影响。具有共光路的 Fabry-Perot 干涉仪对环境干扰不敏感。这对于在普通环境条件下进行精密位移测量是有利的。为了验证和分析这种影响，已经对两种干涉仪（即自制的 Fabry-Perot 干涉仪和商用 Michelson 干涉仪）进行了位移测量，并在各种环境干扰情况下进行了比较。在几种测试条件下，自制的 Fabry-Perot 干涉仪对环境干扰的敏感性明显低于商用 Michelson 干涉仪。实验结果表明，Fabry-Perot 干涉仪中环境干扰引起的误差是 Michelson 干涉仪的五分之一。这证明了具有共光路结构的干涉仪比具有非共光路结构的干涉仪对环境干扰更具独立性。这对于解决普通测量环境中用于精密位移测量的干涉仪的问题是有益的。
