Laser has been widely used in different areas, as requires increasingly higher performance of the lasers frequency stabilization. And the measurement of frequency stability is of great significance to improve lasers performance, in the process of lasers research and development, as well as production.Measurement of He-Ne lasers frequency stability is considered in this paper. Firstly the factors affecting lasers frequency stabilization, the measurement and characterization of frequency stability are discussed. Secondly the measurement system of He-Ne lasers frequency stability is introduced. Besides, the impact of spatial collimation on beat detection is analyzed, and it shows that if two beams of heterodyne detection are unparallel, the angle between them could accept a very small deviation. Then the factors that affect the accuracy of measurement are analyzed, such as, phase difference, polarization, linewidth and frequency drift of the laser, etc. Finally the effect of spots size and overlap ratio on the SNR and the efficiency of heterodyne is discussed, and simulations are carried out. |