This paper presents the application of microstructure replication of lightguiding plate for micro injection compression molding (MICM). The lightguiding plate is applied on LCD of two inch of digital camera. Its radius of micro-structure is from 100μm to 300μm by linearity expansion. The material of lightguiding plate is PMMA. This paper discusses the replication properties for different process parameters by single-parameter method for micro injection compression molding. The important process parameters of replication properties are the mold temperature, compression distance and melt temperature in micro injection compression molding. The mold temperature is the most significant factor of replication properties of microstructure of lightguiding plate for micro injection compression molding.

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The purpose of this paper presents the optical properties of microstructure of lightguiding plate for micro injection molding (MIM) and micro injection-compression molding (MICM). The lightguiding plate is applied on LCD of two inch of digital camera. Its radius of microstructure is from 100μm to 300μm by linearity expansion. The material of lightguiding plate uses the PMMA plastic. This paper uses the luminance distribution to make a comparison between MIM and MICM for the optical properties of lightguiding plate. The important parameters of process for optical properties are the mold temperature, melt temperature and packing pressure in micro injection molding. The important parameters of process for optical properties are the compression distance, mold temperature and compression speed in micro injection-compression molding. The process of micro injection-compression molding is better than micro injection molding for optical properties.

Previous studies have shown that enhancing injection pressure can help improve the precision and mechanical properties of molding products, and reduce their shrinkage. But for now the ordinary hydraulic injection molding machine cannot generally meet the requirements of high pressure injection. To improve the injection pressure, the pressurizing module and the hydraulic circuit were designed, and their influence on the product quality was explored via molding experiments. The relationship between the system pressure of injection molding machine and the injection pressure was demonstrated. The experimental results showed that the maximum injection pressure of the injection molding machine with the pressurizing module was improved from 204 MPa to 320 MPa, up 56.86 %. The lack of materials, bubbles, sags of products were gradually weakened until finally disappeared with increasing the injection pressure. The pressurizing module was convenient to be assembled into or removed from the injection molding machine without damaging the original structure, and the state of pressurizing or no pressurizing could be transformed easily during the injection molding process. These results indicated that this technology was easy to be popularized and applied.