Study Of Air Bubble Defect Detection In Optical Glass Based On Mie Theory

With the progress of science and technology, the application of precision glass components is more and more widely, the quality of glass requirements are also rising.In principle, therefore, improve the glass defects detection accuracy and speed has become an important topic.Using computer system to realize high precision automatic detection now, can greatly improve the efficiency of glass defect detection, save costs and improve industrial earnings.Basic principles and current situation of glass defect detection technology are firstly introduced in this paper, including for the detection of several common schemes, and the principle of a detailed description and graphical representation. In order to improve the detection techniques, Mie scattering principles of micro-sized air bubble are introduced in this paper?Then this article is based on Mie scattering formula and combined with actual application scenario, glass internal air bubble defect is classified as single irrelevant Mie scattering. We concluded that Mie scattering intensity is related with particle refractive index?the refractive index of medium?incident wavelength?particle size? the scattering direction angle and other factors.In practice, unknown parameters will be calculated based on reverse algorithm.On the basis of theoretical analysis, using the finite difference time domain commercial simulation software(FDTD Simulations) for a single micron bubble scattering model for the simulation analysis, by studying the specific intensity distribution within the scope of the scattering angle, using BP neural network algorithm for inversion to calculate the particle size.Finally we set up the experimental platform, a glass sample is shining by a monochrome laser with a wavelength of 532um. The scattered light was measured by a high definition CCD camera. The scattering process can be classified as uncorrelated single scattering according to the properties of optical media. After calculating and smoothing the gray value of split rings of picture, Chahine algorithm was applied to reverse the size of defects.The work of this paper is still in its primary stage, but we can say this study can provide a new thought and a practical research method for glass defect detection and research of air bubble in glass to a certain extent.