石英晶体振荡监控光学薄膜厚度是直接监控光学薄膜物理厚度的方法，与工作波段无关，设置简单，各种厚度皆可控制，易于实现白动控制，将会越来越广泛地应用在光学薄膜厚度监控中。本文首先介绍了石英晶体监控膜厚仪监控光学薄膜厚度的原理，然后讨一论了石英晶体监控仪的发展和晶振片的稳定性。 Quartz Crystal Oscillation Monitoring Optical film thickness is a direct method to monitor the physical thickness of optical films. It has no relation to the working wavelength band and is easy to set up. All kinds of thickness can be controlled and easy to realize white control. It will be more and more widely used in optical film thickness Monitoring. In this paper, the principle of monitoring the thickness of optical film by quartz crystal monitor is introduced firstly. Then the development of quartz crystal monitor and the stability of crystal are discussed.