Study Of A Differential Interference Detection System Based On LabVIEW

In the field of precision machining, the surface characteristic of products must meet the design requirement. There are many surface topography measurements and techniques. Among these techniques, the detection method based on the optical interference theory is widely used, because it has many advantages: non-contact measurement, high precision, adaptability to complicated environment and so on. With the development of science and technology, some computer techniques such as machine vision and image processing are applied in traditional topography measurements. The trend of the surface topography detection technology is to realize the optical and electrical integration in which the computer is the core processing unit.In this thesis, an optical differential interference detection system has been built: the polarization phase shifter and the uniaxial crystal constitute the main part of the optical differential interference imaging unit; the industrial camera and motor systems make up the image acquisition and motion unit; the computer is the core control and process unit. The three units above make up the complete hardware part of the optical differential interferometry detection system.The related software applications based on Lab VIEW have been written. By VISA module configuration, the computer can control the PLC and the stepping motor controller in order to make the linear guide and the polarization analyzer move. By calling the DLL file, the computer can set the industrial camera and control image acquisition process. In image processing, Lab VIEW calls Matlab to implement the related graphic algorithms. Optimize the front panel of VIs to make the GUI interface is simple and easy to operate.By detecting the wafer and optical component with known surface roughness, the resolution and precision of the differential interference detection system meet the design requirement. Under the Lab VIEW program control, the image acquisition and motor unit operates normally. In image processing,the data visualization is conducive to data analysis.