基于迈克耳孙干涉仪光路折叠和抽真空方式测空气折射率

Measuring refractive index of air by Michelson interferometer optical path folding and vacuum extraction

采用光路折叠结合气室先预抽真空后充气的实验方式,改进了传统的迈克耳孙干涉仪测量气体折射率的方法.利用折叠光路法增加激光在气室中的穿越次数达到增加气室内的光程,从而数倍地增强待测信号;采取预抽真空后缓慢向连通气室的大容积缓冲真空室内充入待测气体,使气室内气压更均匀、平稳地增长,从而实现了气体折射率的高精度测量,并验证了气压与折射率的线性关系.

The traditional Michelson interferometer was improved to measure the refractive index of gas by the method of folding optical path combining with pre-vacuuming and aeration of gas chamber.Folding optical path method was used to increase the frequency of laser crossing in the gas chamber to increase the optical path,so as to multiply the signal to be measured.After pre-vacuuming,the gas to be measured was slowly infused into the large volume buffer vacuum chamber connected to the ventilation chamber,so that the gas pressure in the gas chamber increased more evenly and stably,thus the high precision measurement of the air refractive index was realized,and the linear relationship between the gas pressure and the refractive index was verified.