弹流油膜彩色光干涉系统的特性研究

彩色光干涉技术是润滑油膜厚度测量的最有效的方法之一,但对其测量光学理论的研究并不十分透彻。以球-盘弹性流体动压润滑油膜测量装置为对象,建立了彩色光干涉的色度学计算模型,对该系统的干涉条纹和色彩进行了数值模拟与分析。分析结果与实验数据的一致性表明了所建立的模型和分析方法的正确。分析表明:铬膜厚度对图像的色彩和对比度有明显的影响,当其厚度为5～10nm时,能够获得对比度和色彩理想的图像;垫层厚度影响各颜色分量强度分布的初相变;LED光源可产生对比度较好的干涉条纹。

Study on the chromatic interferometry of EHL film measurement

Chromatic interferometry is one of the most efficient methods in the measurement of lubricating film thickness,however the details of the measurement principles have not been well understood.An optical model has been presented to describe the chromatic interference generated by a ball-on-disc configuration in an optical elastohydrodynamic lubrication(EHL) tester,and numerical simulations are presented.The model is validated by the correlation between the analytical results and the lab tests.Simulations show that the thickness of the Cr films has significant influences on the colors and the contrast of the interferences fringes,and a thickness between 5~10nm can give favorable measurements.The thickness of the spacer layer may change the initial phase of the intensity curves of the color components.Moreover,the simulation by a LED light source shows that the colorful interference fringes have more sharp constrast than a traditional cold light source.