Fabrication of Microlens Array on Disk UsingMicro-Injection Compression Molding Process

• Main Authors: Ting-Yu Cheng, 鄭廷裕
• Other Authors: 楊申語
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/f9ru6b

碩士 === 國立臺灣大學 === 機械工程學研究所 === 105 === The double-sided microlens array is a key optical component of the light field camera, the micro projector and the near eye display etc. To enhance the productivity, this study developed a design of wafer-level double-sided microlens array. In this study, Moldex3D simulation analysis software was used to simulate the design between traditional multi-cavity and disc mold. The result shows that the disc mold can save plastic and molding time. The 4-inch disc with double-sided microlens array can greatly enhance the production efficiency. The four most sensitive processing parameters of injection molding (IM) and injection compression molding (ICM) for microlens disc were discovered. Then L9 orthogonal method of Taguchi method was employed to find the best combination of molding parameters. For molding experiments, 2 mold inserts with 4×4 convex and concave lens array were machined by the high-precision three-axis machining center. They were mounted into molds in one of two locations: one close to gate and the other away from gate. The mold was designed to be used in both IM and ICM. The molding experiments confirmed that the ICM is better than the IM with higher precision and lower residual stress. The results of experiments confirmed the results of simulation. The ICM molded microlens array has focal length 2.549 mm and spot size 50μm.   This study compared the simulation analysis and molding experiment in IM and ICM. ICM process successfully produced the double-sided microlens array on the 4-inch disc with high precision, low residual stress and good optical quality. This study proves the feasibility of fabricating wafer-level double-sided microlens array using injection compression molding.