1. Tianjin University, Tianjin 300072, China
2. National Institute of Metrology, Beijing 100029, China
3. Beihang University, Beijing 100191, China
4. Beijing Standard Quality Monitoring Center for Electro-mechanical Products, Beijing 100027, China
Abstract：A micro-optical path measurement system based on the principle of multi-beam interference using two channels is introduced. The system that can measure the micro-change of optical path caused by the change of air refractive index has high measurement sensitivity. And the measurement sensitivity can be verified by a simple experiment, which uses the acoustic wave to change the refractive index of the air and further change the optical path length. The experimental results of the system are compared with those of the Michelson interference method. It is concluded that this system can achieve high measurement sensitivity with small interference arm, while the Michelson interference system are in the case of the large interference arm. The measurement of the optical path variation can be applied in many fields, and the experimental system has the characteristics of miniaturization, which can provide the technical basis for the application in the related fields.
2018, Vol. 39 
