射出成形光學鏡片之雙折射分析

Analysis of Birefringence in Optical Lenses for Injection Molding

林士銘(Shih-Ming Lin)

指導教授 ： 王培仁

國立清華大學/工學院/動力機械工程學系/碩士(2006年)

摘要

光電產業蓬勃發展帶動光學零組件需求大增，光學透鏡為常見之光學元件，可分為光學玻璃與光學塑膠兩類，本研究主要探討塑膠加工於光學透鏡之成形，其加工方法為射出成形；射出成形為成本低、速度快、良率穩定、生產效率高之一次成形加工技術，用於光學塑膠透鏡成形不需拋光、研磨之二次加工，生產時間縮短與成本降低為其優勢。然而，塑膠透鏡於射出成形往往伴隨雙折射現象存在，產生之光程差已無法透過組合透鏡等方法做矯正，檢測時雙折射過大即為廢品，此為射出成形極待解決之問題。

因射出成形鏡片之光學品質主要由幾何誤差與殘留雙折射所構成，本文使用實驗設計法針對光學透鏡幾何誤差與雙折射影響因子分析探討，為提高良率、節省物料成本與成形時間，射出成形因子分析以確保鏡片幾何尺寸與降低雙折射實重要關鍵，同時以結合模流分析與光學模擬，期能藉光學模擬即能預測成形之鏡片光學品質。

關鍵字

雙折射 ； 殘留應力 ； 實驗設計 ； 射出成形

並列摘要

As the prosperous growth in electro-optics industry, the demand on optical components has grown significantly as well. Among the optical components, optical lenses are typically categorized as either plastic or glass type. The objective of this study is to investigate the injection molding of plastic lenses which are known for the process with low cost, high volume, good yields, and high efficiency. Plastics lenses do not need polishing and relevant post processing steps which results in reduction of production times and costs. Nevertheless, birefringence embedded in the lenses have made the optical path difference in lens components too large to be compensated so that scraps becomes a major problem in the industry which needs to be resolved today.
Because the optical qualities of injection molded lenses consist of geometric errors and residual birefringence, analysis of contributing factors are conducted with experimental methods for efficiency improvement, cost reduction, and time saving. The key is to get hold of process control factors for combining the optical analysis into flow analysis programs so that optical qualities can be successfully predicted.

並列關鍵字

Birefringence ； Residual Stress ； Experimental Design ； Injection Molding

參考文獻

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