Modeling and analysis of multi-shot injection molding of Blu-ray objective lens

The Blu-ray objective lens is one of the electronic parts that has an important role in data storage in such a way that its production requires a high level of accuracy. One way to produce the Blu-ray objective lens is by means of a micro-injection molding technique. We investigated the effect of insert part in a multi-shot injection molding on the shrinkage after the process of injection. An aspherical shape is made for the insert part of the Blu-ray objective lens, then compared with single-shot injection molding. Zemax software was used to design the Blu-ray objective lens, while Moldex3D software was applied to analyze the flow of material into the mold during the injection process. The Taguchi method was used to determine the best parameters to obtain the minimum shrinkage values of the injection processes of both multi-shot injection and single-shot injection molding techniques. Based on the observations, it is clearly evident that the multi-shot injection molding process has a lower displacement value compared to the single-shot injection molding, namely, 0.0161 mm compared to 0.0550 mm and also the multi-shot injection can save the cooling time 5 seconds faster than single-shot injection molding. So, this can favorably improve the production of the injection process for the material in the form of the micro part.