Research Of White-light Scanning Interference System Of Ultra-precision Machining Surface

The continuous development in the field of modern national defense industry,aerospace, automobile manufacturing, the increasing requirement of ultra-precisionmachining parts, as well as the continuous miniaturization and refinement trend ofmachinery parts, electronic devices, and optical components has put forward higherrequirements to the topography detection technology of ultra-precision machiningsurface. Through the analysis and comparison of the methods in surface topographymeasurement of ultra-precision machining parts, this paper adopted the high precisionmeasurement method based on the white light scanning interference measuringprinciple. Conduct the white light scanning measurement of the surface to bemeasured, record the interference signal of each point on the measured surface indifferent optical path difference position, use white light interference signal peakextraction algorithm to get the zero optical path difference position from theinterference signal of each point respectively, then receive the height information ofeach point on the surface to be measured.This paper carried on the thorough research on the white light scanninginterference measuring method and system, in order to realize the high precisionmeasurement of ultra-precision machining surface. Research work mainly includesthe following aspects:1. According to the characteristics and principle of white light interference,analyzed the different types of white light scanning interference signal processingalgorithm, based on the analysis and comparison of all kinds of algorithm, proposedan improved algorithm combined phase shift method and Morlet wavelet transform,carried out verification and confirmed that the improved algorithm is more suitablefor actual measurement experiment.2. Designed the white light scanning interference measuring system, mainlyincluding the design of scanning way, interference microscope, micro displacementdevice, optical imaging system, white light source, image acquisition device.3. Analyzed the process of white light scanning interference measuring,completed the design of the system software, and realized the automatic control ofmeasurement process. 4. Carried out repeatability measurement experiment using the white lightscanning interference measuring system, get the repetitive measurement precision ofthe measurement system.5. Conducted the white light vertical scanning interference measurement of thegauge block and the hyperboloid, verified the accuracy of the measurement system,analyzed the error of the measuring system and put forward the correspondingcompensation method.