Multifunction Surface Measurement System Based On Focusing Optical Stylus Interference And Confocal Image

Surface morphology has a significant impact on working capability of part such as wearability, copulate precision and so on, so surface topography measurement and analysis plays a great role in product quality improve and process control. Nowadays,most surface topography measurement instruments have single measurement method and have inevitable defects. A noncontact measurement system based on focusing optical stylus interference and confocal image is researched in this paper, it can measure different kind of surface.Main outlines of this dissertation include:1. A surface morphology measurement method based on focusing optical stylus interference and confocal image is researched, the measured performance and influence factors of this method are analyzed. The lateral resolution of focusing optical stylus interference method is 1.3?m, vertical resolution of 5nm. The lateral resolution of confocal image is 0.5?m, vertical resolution of 1.5?m, horizontal measurement range of0~40?m.2. A multifunction surface measurement system is developed, the key components of the measurement system are designed. Multifunction measurement sensor has two functions of focusing optical stylus interference function and confocal image function, it is based on Linnik interference microscopy, by adding reference path or not, it can realize two different kinds of measure functions. A three-dimensional measurement system is designed, the vertical scanning system is driven by piezo-electronic transducer and controlled by transmission grating standard measuring system, vertical resolution of 1nm and vertical measurement range of 0~40?m. The two-dimensional stage with the common baseplane are driven by stepper motor, its displacement resolution is 0.2?m and range is30mm×30mm.3. The displacement performance of vertical scanning system and two-dimensional stage is tested and analyzed. The positioning accuracy of two-dimensional and vertical scanning system, and the straightness of two-dimensional stage are tested by Agilent5519 B double-frequency laser interferometry, the test results show that the driving system meet the requirements of the measurement system.4. A measurement and evaluation software system is developed for the multifunction surface measurement system. Testing and certification to indication error and repeatabilityof the measurement system is done, and the typical samples are measured. The test results show that this system can used in engineering area to measure different kind of surface topography.