Study On Multi-Parameter Detection Technology Of 3C Product Glass

With the popularization and development of 3C(computer,communication,consumer electronics)products,the geometric parameter detection of glass components used in 3C products has become an indispensable part of 3C products.And in order to obtain higher production efficiency,the requirement of multi-parameter simultaneous detection of 3C products glass is put forward.At present,the instrument for simultaneous measurement of multiple parameters is an image measuring instrument with a laser displacement sensor or a white light confocal sensor,in which the image measuring instrument is used for two-dimensional size measurement,and the laser displacement sensor or white light confocal sensor is used for thickness measurement.Although this instruments have high detection efficiency,due to the greatly differences in the detection schemes of two-dimensional size and thickness parameters,the integration of the system is not high,the system is complex and the cost is higher.In order to solve the above problems,this dissertation focuses on the high-precision multi-parameter simultaneous measurement scheme of 3C product glass.An edge detection method based on the defect spot mode of position sensitive detector is proposed,and a high-precision online automatic measurement method of glass size is proposed by combining the above edge detection method with the electronically controlled displacement stage.The corresponding systems are developed,the feasibility and practicability of the methods are verified through a variety of experiments and research work.On this basis,the size measurement scheme proposed in this dissertation is integrated with the thickness measurement scheme based on laser triangulation.A highly integrated multi-parameter simultaneous measurement scheme using a single light source is proposed,through the time-division multiplexing of optical path and detector.The innovative research achievements achieved and works in the dissertation are as follows:1.An edge detection method based on defect spot mode of position sensitive detector is proposed.With the output characteristics of the PSD in the defect spot mode and the size transformation properties of a focused beam,edge detection sensitivity can be improved.Under the set parameters,the accuracy of the system for the object edge detection reached20 nm,and this method is characterized by simple system and high precision detection.2.A high-precision online automatic measurement method of glass size is proposed by combining the above edge detection method with the electronically controlled displacement stage.The edge recognition signal given by the edge detection method is used as the counting switch of the driving pulse of the electronically controlled displacement stage.Under the set experimental parameters,the size detection resolution can reach 0.6 μm,the size detection accuracy is better than 18 μm.This method has the advantages of large measurement range and simple system structure.3.The glass thickness measurement scheme based on laser triangulation method is proposed and verified,and integrated with the aforementioned size measurement scheme.A highly integrated high-precision multi-parameter simultaneous measurement scheme for glass of 3C products is proposed.The parameter measurement methods in this scheme are based on laser collimation measurement technology.A single semiconductor laser can be used as the light source,and the optical path and detector can be time-division multiplexed,which greatly simplifies the system structure and reduces the cost.