针对锁相热波成像技术在涂层厚度检测上的应用，简介了锁相热波成像技术基本原理，通过理论曲线分析了涂层厚度与相位的关系，结果表明采用锁相热波成像技术可有效测量涂层厚度。介绍了自行设计开发的锁相热波成像涂层检测系统，利用该系统对涂层试件进行了检测试验。结果表明：锁相频率为0.17 Hz时，对于20～150 μm涂层厚度的检测的重复性好，相对标准误差在2.5%以内，对红外热像技术在涂层测量领域的应用具有指导意义。

For the applications of Lock-in thermal wave imaging technology, the paper is focused on its theory, simulation and experiment. The relationship between the coating thickness and phase was analyzed through the theoretical curve. It was concluded that coating thickness had a linear proportional relationship with the phase in a certain thickness range, and calculation results show that Lock-in thermal wave imaging can effectively measure the coating thickness. The phase locked thermal imaging detection system was developed for coating thickness measurement, and the system was used for coated specimens. The experimental results show that the PLL frequency is 0.17Hz for the detection of 20-150 μm coating thickness with good repeatability and the relative standard error is less than 2.5%. This paper has guiding significance for the application of infrared thermography in the field of the coating measurement technology.