以光學干涉技術探討透明薄膜之變形特性

Investigation of Deformation Behaviors of Transparent Films by Optical Interferometry

陳柏宇(Po-Yu Chen)

指導教授 ： 徐烱勛

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2011年)

摘要

近年來，軟性顯示器之發展已受到外界之高度注目，藉由可撓曲特性成為新一代顯示器之革命，但軟性顯示器經長時間之變形下容易使得內部透明薄膜材料產生破壞與損毀，因此，對於薄膜的力學問題探討為相當重要之課題。
本文首先建立杜曼-格林干涉儀(Twyman-Green Interferometer)，將變形透明薄膜置於干涉儀路徑當中，透過薄膜變形理論及變形幾何關係求得光程差之推導，發現杜曼-格林干涉儀之條紋即為物體變形撓曲角度的等高線，利用四步相移術獲得帶有薄膜撓曲角度之相位分布，並以積分技巧獲得透明薄膜之全域性變形量。
為了驗證本文所建立光學干涉量測系統，首先需以驗證此方法之可行性，因此，以設計一已知尺寸的弧形模具並將透明薄膜黏貼於其上，介於驗證本文所提出方法之正確性，此外將以利用本文建立之量測系統量測出透明薄膜變形量，並比較已知尺寸確定此方法之準確性。此外，針對透明薄膜於承受彎曲負載下之力學特性做研究，將比較不同變形之循環彎曲次數下薄膜的殘留變形、光穿透率及電阻值。

關鍵字

軟性顯示器 ； 透明薄膜 ； 杜曼-格林干涉儀 ； 殘留變形

並列摘要

Owing to a flexible transparent optically substrate such as PET has flexible, high resistance to impact, and superior transmittance properties, it has been one of the best candidate of substrate materials for the development of further flexible displays. In practice, there has been the transparent conductinAbstract
Owing to flexible films such as PET have flexible, high resistance to impact, and superior transmittance properties, it has been one of the best candidate of substrate materials for the development of further flexible displays. In practice, there has been the transparent conducting film (TCO) such as ITO film deposited on the substrate. The constituent material of flexible films is polymer and its mechanical properties are significantly different than those of TCO film. Therefore, the considerable residual deformation may be generated due to the mechanical mismatch between the film and substrate. However, flexible films has high transmittance and large deflection features, and this makes that the present laser interferomery used only for the non-transparent objects under small deflection cannot be employed to investigate this issue. To overcome this limitation, in this thesis, an optical measurement technique based on Twyman-Green interferometry was established to measure the full-field displacement distribution of flexible films under large deflection. Furthermore, a mechanism was designed to apply a bending loading on the transparent film. The influence of bending cycle on deformation was investigated and it was found that the residual deformation increases with increasing bending cycle.

並列關鍵字

flexible films ； transparent conducting film (TCO) ； residual deformation ； Twyman-Green interferometry ； bending loading

參考文獻

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