軟性顯示器之可撓特性量測研究

Abstract

相較於可撓電子產品，硬式電子產品已不能滿足人們的舒適與方便的生活型態。可撓顯示器是具有輕、薄、可撓與耐衝擊的顯示器，它在未來將成為一種熱門的電子產品。例如，可撓顯示器是具有和紙張一樣的互動能力之潛力。撓曲可撓顯示器可以當作是一個有效率的輸入技術，就如同在硬式顯示器之按鈕控制來執行導航、內容選擇、聽接電話、聽音樂和閱讀書籍等功能。因此，可撓顯示器的撓曲特性測試將會扮演相當重要的角色，尤其在目前的研究和生產階段。本研究的目的即是提出一個新的可撓特性檢測系統（FCIS），來為可撓顯示器在不同彎曲的條件下，測量其彎曲下之特性。為了量化彎曲條件，利用電荷耦合器（CCD）的最佳化快速反應滑動模式控制（OFRSMC）方法將是用來做可撓顯示器的曲率半徑之回饋控制。在可撓顯示器的製程中，針對可撓基板的薄膜沉積上之全域式殘留應力檢測是一個很重要的議題。因此，本研究提出利用共光程干涉術與平面大區域之扭轉式向列型液晶調變白光源的一個新穎性全域式殘留應力分佈檢測方法。最終，本新的技術測試平台，成功的利用OFRSMC的FCIS與全域式液晶調變共光程干涉術來針對可撓基板在彎曲多次後，來做其電性、光學和機械特性的檢測。除此之外，針對曲面顯示器的影像品質分析，本研究提出針對曲面顯示器的人眼視覺角度之邊界對比失效分析(ECFA)。為了分析曲面下之影像邊界對比，一個可撓膽固醇液晶顯示器將藉由FCIS來撓曲至不同的撓曲半徑，並藉由一個電荷耦合元件(CCD)亮度色度計來模擬人眼，以便分析在不同曲率半徑下之曲面影像的人眼最大視覺角度。因此，反覆撓曲下之可撓顯示器的電性、光學與曲面影像品質特性之檢測結果，將有助於可撓顯示器之設計或其製造商來開發出具有人眼視覺大角度與便利的可撓顯示器產品。

In contrast to flexible electronic products, hard electronic products can not satisfy people who demand a comfortable and convenient lifestyle. Flexible display is light, thin, flexible, and shock-resistant. It will become a promising product in the days to come. For example, flexible displays potentially allow for interaction styles that resemble those used in paper documents. Bending of a flexible display can be as effective and efficient an input technique as button controls in rigid displays for tasks like navigating through icons, selecting contacts and making phone calls, playing music, and reading a book. Therefore, testing of flexible displays for bending characteristics will play an important role in research and production. The objective of this study is to present a new flexible-characteristics inspection system (FCIS) for measuring bending characteristics of the flexible displays under different bending conditions. In order to quantize bending conditions, charge-coupled device (CCD) optimal fast-response sliding-mode control (OFRSMC) is utilized to control radii of curvature of the flexible displays. For flexible displays in manufacture, the full-field residual stress inspection for films deposited on flexible substrates is an important issue. This study proposes a novel method of the fast full-field residual-stress distribution inspection with a flat large-area twisted nematic liquid crystal modulator based on a white light source by using a common-path interferometry. As a result, the new technique successfully measures electrical, optical, and mechanical characteristics of flexible substrates up to several bending times by using a FCIS based on OFRSMC and a full-field liquid-crystal modulating common-path interferometry. In addition, to analyze image qualities of curve displays, this study presents edge contrast failure analysis (ECFA) method on the vision angle of human eyes for curve displays. In order to analyze edge contrast of curve display images, a flexible cholesteric liquid crystal display is bent for different radii of curvature by using an FCIS. To simulate the human eye factors, a charge-coupled device colorimeter is utilized based on ECFA to analyze a maximum vision angle of human eyes with respect to curve displays under different radii of curvature. Inspection results of electrical, optical, and mechanical characteristics after repetitive bending, and image-quality characteristics in bending depicted on flexible display help a designer or maker of flexible display design large-vision-angle and comfortable flexible-display products.