液晶顯示器在運輸過程或車用顯示器易因隨機振動而造成結構的破壞。本文以有限元素軟體ANSYS進行液晶顯示器之模態分析與隨機振動分析,模擬不同的夾持方式與振動方向對顯示器所造成的影響,比較顯示器以背後固定、上下固定或左右固定時的自然頻率與模態振型,並計算顯示器承受隨機振動時所產生的能量頻譜密度(PSD)與加速度均方根值(Grms),藉此探討不同固定方式在隨機振動環境下所產生振動特性之差異。經由模擬結果顯示,液晶顯示器在隨機振動環境下左右固定產生的振動是最小的;而以不同的吊架孔孔距作背後固定也會影響顯示器之振動特性,承受X、Y軸向振動時,以100 x 100 mm的吊架孔距作背後固定產生的振動最小,承受Z軸向振動時,以75 x 75 mm的吊架孔距作背後固定產生的振動最小。
It have more random and unstable vibration when vehicles moving. Long-term vibration will cause the electronic components of the liquid crystal display monitor to produce fatigue damage. Structural deformation is because of vibration and thus the occurrence of stress and strain. Stress and strain is proceed with some frequency, and over time will cause structural fatigue damage or noise. In this paper, we use finite element software ANSYS to proceed modal analysis and random vibration analysis to compare the influence of difference fixed method and vibration direction of LCD. We discuss natural frequency and modal shape of LCD with different fixed method, and calculate their power spectral density (PSD) and root mean square of acceleration to compare which one fixed method is better.