- 學位論文
探討射出成型製程於薄型化導光板光學性質影響 之研究
Study on the Influence of Process Parameters of Injection Molding on the Optical Performance of Thin-Wall Light Guide Plate
摘要
隨著平面顯示器產業的迅速發展，液晶顯示技術和顯示影像產品 追求更輕、更薄的趨勢與優良的品質表現。背光模組組件中，導光板 是控制亮度及均齊度的重要元件，其主要技術包含微結構光學設計與 成型能力，其主要技術包含了微結構基礎設計與成型能力，若能藉由 實驗歸納出品質影響趨勢，並找出導光板最佳設計準則，將能有效的 節省時間與發光效能的提升，進一步促進產品品質與產業競爭力。 本論文研究以長80mm、寬60mm 搭配0.6mm、0.9mm 及1.2mm 三種厚度變化之射出成型導光板，以實際射出成型來參照比對不同製 程參數對於微結構之複寫性與間的變化，量測出微結構之複寫率與導 光板殘留應力；再以輝度計量測實際導光板之光學輝度分佈，討論不 同厚度以及成型參數導光板微結構複寫率對光學品質的趨勢。 由研究結果顯示，薄型化導光板微結構複寫率會隨於模具溫度、 熔膠溫度、射出速度等增加而提升；越高的熔膠、模具溫度與射出 速度會有較低殘留應力。複寫率與光學輝度間驗證結果，設定相同 製程條件下(模具溫度110oC，熔膠溫度320oC)，射出速度由300mm/s 提高至1200mm/s 時，在厚度1.2 mm 導光板，複寫率增加1.62%， 平均輝度值增加113 nits，在厚度0.9 mm 導光板，複寫率增加1.66%， 平均輝度值增加113 nits，在厚度0.6 mm 導光板，複寫率增加1.88%， 平均輝度值增加128 nits，由此可得知微結構複寫率的增加，可以對 光學輝度有進一步的提升。本研究充分顯示了不同微結構成型性對 於導光板之發光性能的差異，可作為相關產業研究人員進行設計與 製造時的參考。
並列摘要
With the rapid development of flat panel display industry, liquid crystal display technology and display products; the pursuit of lighter, thinner trends and superior performance is increasing in demand. The light guide plate, one of the backlight components, is an important component to control the brightness and homogeneity. Its main technologies include micro-optical structure design and molding capabilities. Observing the influence factors by an experiment in order to achieve the optimum light design strategy for light guide plates will efficiently reduce time and improve luminous efficacy, moreover, promoting product quality and industrial competitiveness. In this study, light guide plates are injection molded at length 80mm, width 60mm with three various thicknesses; 0.6mm, 0.9mm and 1.2mm. Comparisons are made from different process parameters in actual injection molding effects on replication of micro-structure and are examined by measuring the replication rate of micro-structure and the residual stress of light guide plate. Next, this study uses a luminance meter to measure the optical brightness distribution of the light guide plate. Lastly, this study discusses the varying thickness and process parameters affecting the replication rate of the light guide plate and tendency of the microstructure optical quality. This study showed that the replication rate of micro-thin light guide plate structure increase with the in-mold temperature, melt temperature and injection speed. In opposite, residual stress is decreased. Validation results between replication rate and the optical brightness, under the same process conditions (mold temperature 110oC, melt temperature 320oC), increased injection speed from 300mm/s to 1200mm/s, as the light guide plate of thickness 1.2 mm, the replication rate increase 1.62% and the average luminance value increased 113 nits; at thickness 0.9 mm, the replication rate increase 1.66% and the average luminance value increased 113 nits; at thickness 0.6 mm, the replication rate increase 1.88% and the average luminance value increased 128 nits. As the result, the optical brightness improved as the replication rate of micro-structure increased. This study demonstrated that different micro-structure molding properties cause different luminescent properties of the light guide plate. This result can be a reference for related industrial research in design and manufacturing.