Chromatic Confocal Three-dimensional Topography Measurement System Based On Color Spatial Modulation Technology And Experimental Research

In this paper,the research of chromatic confocal technology for three-dimensional topography measurement of the surface of the object is carried out.The principle of chromatic confocal measurement is analyzed in detail,and the key optical element of the chromatic confocal system-the dispersive objective lens,is designed.The chromatic confocal topography measurement system is successfully constructed and used to measure and restore the microscopic three-dimensional topography of the object surface.Use a color camera instead of a spectrometer as a data receiving device for a chromatic confocal system,which is more beneficial to industrial use;With the research of digital micro-mirror devices(DMD),it lays the foundation for the research of parallel chromatic confocal technology basis.The main research contents of this paper are as follows:(1)Analyze the basic principles of chromatic confocal technology,and analyze the main factors affecting system performance.According to the requirements of the task,a key component of the system-the dispersion objective lens,is designed and optimized.Based on the rational selection of hardware,a set of chromatic confocal three-dimensional topography measurement systems is built.The system has a sub-micron measurement accuracy under the 4x objective lens.The range reaches1100 ?m.(2)In order to save system cost and facilitate system integration,a color camera is used instead of a spectrometer as a collection device for chromatic confocal data.Aiming at the problem of the axial information calibration of the color of the color camera image,a color conversion algorithm was proposed,and the image processing and data processing algorithm design of the measurement system was completed.(3)The chromatic confocal three-dimensional topography measurement system is used for experimental research.The accuracy of the color conversion algorithm was verified through calibration experiments;the axial measurement capability of the system was verified through step height experiments;and the ability to restorethe three-dimensional topography of the object surface was verified through a shape reduction experiment on the coin surface;DMD has completed a parallel chromatic confocal measurement experiment to verify the feasibility of the color camera and color conversion algorithm for parallel chromatic confocal technology.