Defect Detection System For Optical Thin Film Based On The ARM Of Microscopic Imaging

Optical thin film and its products have been widely used in various fields. The surface roughness of optical thin film has a very important influence on the optical properties such as refractive index, surface scattering and so on. In the process of production and processing, the surface of fine scratches, stains, burrs and other will affect the performance of the products, therefore the process on the surface of the parts of real-time and accurate defect detection has important significance. The traditional manual visual inspection method has the disadvantages of large labor intensity, low accuracy, low efficiency, poor reliability, and so on. It can't adapt to the needs of the development of modern production to the miniaturization of intelligent. In view of the on-line detection of the surface defects of the optical thin film, the on-line detection system based on ARM processor is designed. The system has the characteristics of on-line, real-time and non-contact, which is very important for ensuring the quality and improving the production efficiency of the optical thin film products. CMOS image sensor IMX135 is used as digital microscope image acquisition part. Through the CSI-2 interface, the image is transferred to the ARM processor. The images are processed and stored in the ARM processor. The image is processed and stored, and the image is transferred to the LCD screen by HDMI interface. This thesis mainly completes the following work:(1)The overall design of the embedded micro imaging system is completed, including optical lens module, CMOS image acquisition module, image transmission display module and the upper computer image processing module.(2)Research and design the optical connection system of the micro imaging module, complete the optical system's field of view matching design. According to the requirements of the system resolution, the system of microscope objective lens and the adapter are designed and simulated by using ZEMAX software. The classification and characteristics of the illumination of the microscope are studied. The design of the reflective lighting scheme is designed.(3)The core board of the micro imaging is designed. The micro image acquisition board is designed with the image sensor of SONY IMX135. The peripheral driving circuit and power supply matching design are designed with the output interface of CSI-2 MIPI.(4)Analysis of the microscopic image acquisition hardware design scheme and the raspberry pi as the ARM processor platform, the design of the camera under Linux system driving program and image acquisition and processing software collection plate image transmission through a CSI interface to the raspberry pi processor, image enhancement and filtering of image processing algorithms for image processing.(5)The experimental verification of the embedded micro imaging system based on ARM is carried out, and the accuracy of the system is verified by different light source, and the accuracy of the system is verified.