The Research Of Non-contact Measurement Technique Of The Toughened Glass’s Surface Topography

Toughened glass’s surface shape profile can be changed by bending device in theprocess of production, thus it can be applied to various occasions of surface shape profilewith special requirements. At present, the prefabricated form can usually used to detect thesurface shape surface parameters of the glass which can be bended.. But, using prefabricatedform can have low precision and efficiency. For the above problem, the surface shape profile‘s measuring method of the glass which is bended is studied in this paper. Line structure ofthe laser’s projection imaging detection method is used to sample and measure the glassproduct at many cross section, in order to reconstruct its surface shape profile to measure theglass product’s shape profile parameters with non-contact technique.In view of three-dimensional imaging principle of the line-structured light, the imaginggeometric model is established; on the basis of it, the experiment system is built to calibratethe parameters in the model; in the view of the problem that the difference of the reflectedlight intensity is bigger in the field which is caused by divergence angle of the line-structuredlight、edge intensity of laser’s line center and normal direction difference of the surface of theglass, the enhancement algorithms of the laser stripe information are studied; for fuzzyproblem of the line edge which is caused by vignetting projection of the laser line edge andparasitic light, the extraction algorithms of the center line are studied in order to realize theaccurate extraction of stripe center line; for the reconstruction process of the surfacemorphology of glass product, the curved surface fitting methods are studied; and on the basisof obtaining discrete data points, the least squares surface fitting is used to reconstruct thesurface topography of glass product, and the error of the algorithm is analyzed; finally, basedon the reconstruction of the surface morphology, the curvature of the points on curved surfacefitting is calculated to carry out non-contact measurement in parameters of the position of theglass product.