Design and Implementation of Optical Inspection System for Curved Lens

• Main Authors: WANG, HSIN-PO, 王信博
• Other Authors: LIN, KEH-MOH
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/j7ych9

碩士 === 南臺科技大學 === 機械工程系 === 104 === Currently, the quality inspection of curved lenses is conducted piece by piece and manually. However, it is time- and labor-consuming. If the inspectors work for a long time, their eyes will be damaged because they have to examine the lenses under strong light. Hence, if the inspection of curved lenses can be automatized, it not only greatly reduces the inspection time but also the labor cost. This study is divided into three parts. The first part is the design and fabrication of an optical inspection system and the testing the resolution of this inspection system. The second part is the writing of an image processing program: by using image processing technology, curved lenses images are analyzed in order to highlight positions of blemishes. The third part is the application of the motor control technology to construct a curved lenses transport system. Finally, the image analysis system and transport system are integrated on a user interface. The results show that the image processing technique can successfully identify the scratches and stain blemishes on lens, but the resolution of the system is still not enough to detect residual traces of strengthening liquid. In addition, for seeded region growing (SRG), the selection of threshold values and morphology analysis methods are important parameters for image processing. Although the gradient method is more time consuming, but it can analyze each image of one specimen in less than three seconds while the total analysis time of one image is less than six seconds. The integrated system developed in this study can complete the following procedures: curved lens transportation, lens image capture, lens blemish inspection, and lens classification. It can be used as the foundation for future development of an automatic inspection system.