TFT-LCD具有高精度、高單價之特點，在產品物流運送過程中，可能受到振動、衝擊、掉落等機械力，使產品造成損壞。在產品環境測試項目中，包覆有緩衝包裝材料之掉落測試造成的衝擊最為劇烈，本研究即以此為探討對象。研究之宗旨為使產品於設計初期，即能評估整體結構於掉落試驗下之衝擊響應，研究中將以有限元素法進行數值模擬，並與實驗數據進行比對，以獲得有效之分析模型，並建立完整的掉落試驗數值模擬及分析模式。 研究之進行分為掉落試驗及數值模擬兩大主軸，掉落試驗為量取主要構件之衝擊加速度、動態應變及落下角度等相關數據；數值模擬方面，使用有限元素分析軟體LS-DYNA進行分析，將與實驗條件相同之邊界及初始條件代入分析模型求解，獲得模擬之衝擊加速度與動態應變量；隨後與實驗數據進行比對，以驗證有限元素模型之正確性。 在有限元素模型經合理性驗證後，即進行國際電工協會(International Electrotechnical Commission, IEC)法規之全方位掉落測試數值模擬；檢視各構件於試驗中之應力分佈及損壞模式，得知試件於face_4測試，將使金屬前框與塑膠底板產生塑性變形；而face_6測試中，試件則產生更劇烈之損壞，致使液晶模組與塑膠外殼鎖附處產生脫離，使產品無法通過IEC法規測試。研究中對於產品損壞模式現況，分別對於金屬前框、塑膠底板與塑膠外殼等，提出三種設計改善方案，有效改善塑性變形與液晶模組脫開現象，使產品通過IEC法規測試。 應用本文採用之分析評估模式，可有效預測產品於掉落試驗中之衝擊行為，幫助設計者於開發初期預估產品強度、發掘並改善問題，以縮短設計開發時程及降低成本，進而提高產業競爭力。 The study aims at developing a reliable and effective simulation and validation technique for opto-electronic display instrument, i.e., TFT-LCD with EPE foam, under drop environmental stress influences. Traditionally, the development and improvement of a product design is in the process of trial-and-error cycles, which is rather time-consuming. The establishment of analysis and validation techniques conducted in the study can consider environmental suffering on TFT-LCD during shipment in design and development stage. In the study, finite element modeling (FEM) will first simulate TFT-LCD under the suffering of drop. Subsequently, drop test will be conducted and some sensoring data such as dynamic strain, impact load and vibration acceleration will be acquired for both validating FEM simulation and modifying numerical model. An effective simulation and validation technique can be yielded after the cycles of simulation and experimental test efforts. This numerical modeling validation can decrease development due time, make cost down, and improve design capability of domestic TFT-LCD products.
