應用於有機顯示器具高正向亮度且消除模糊效應之微梯形陣列結構膜設計

Abstract

關於有機發光二極體(OLED)應用於平面顯示器用途，目前待解決的問題是在出光效率低下的部分，因此在元件的玻璃基板表面貼附一層微結構陣列，目前已確定是可大幅增加出光效率的一種方法。然而對於顯示器的畫素而言，其影像會因為其正上方微結構耦合自鄰近畫素的光跡，導致畫素間的模糊效應產生。 在本論文中，我們經由光學模擬軟體LightTools®對光線進行幾何追跡的方 法，採用一種與畫素對準貼附的微梯形陣列膜層(mTAFs)，確保當有機發光元件維持較高的出光功率同時，能透過配合發光元件規格以調變微梯形的結構參數，使其在正向視角的觀察下能夠消除畫素間的模糊效應，並且進一步提升個別畫素在正向亮度方面的效益。在玻璃基板厚度450 μm、個別畫素尺寸 、間距100 μm的條件下，可使有機發光元件的發光功率效率獲得61.5%的增益，並且具有消除模糊效應後最佳為2.59倍的正向亮度值。 我們更配合一主動矩陣有機發光元件(AMOLED)的實際規格再行設計，並選取先前研究的中央鏤空式微透鏡陣列與微梯形陣列作出比較。然考量到觀測視角傾斜下的亮度分布結果，會發現當微結構在特定的水平位置上，仍有遮蔽畫素並造成其相互干擾的現象。因此在最後也總結了應用於顯示元件上的微結構設計理念，乃至達成全角度耦合的方面，實質上是有待進一步改善的。

In the application of flat-panel display, the problem to be solved on organic light-emitting diode (OLED) is low out-coupling efficiency. It has been confirmed that micro-structure attachment on the surface of glass substrate is a beneficial method for raising the light extraction efficiency. However, for the pixels of display, their image may well encounter blur effect among themselves due to the adjacent light-tracing from the above micro-structure. In this thesis, we simulate for the optical model through optical simulation software LightTools® by using the method of geometric ray-tracing. As applying an attachment of micro-structured trapezoidal array films (mTAFs) with pixel-alignment, we can ensure that the OLEDs maintain a high output optical power as well as enhance the gain of luminance intensity at the normal direction with removing blur effect, which fits the specification of device itself by tuning the parameters of the structure. Under the condition of glass substrate thickness of 450 μm, the respective pixel size of , and pixel spacing of 100 μm, it allows the luminous power efficiency of the OLEDs to obtain an enhancement 61.5%, and can reach the best value of 2.59 times the gain of luminance intensity with removing the blur effect. Furthermore, we arrange another design for the actual specification of an active-matrix organic light-emitting diode (AMOLED), and select the previously researched center-hollowed microlens array films (MAFs) to make a comparison. However, as we consider the results of luminance distribution under the different oblique viewing angles, it reveals that the micro-structure on the specific position still suffers from the phenomenon of crosstalk. As a result, we finally have a summarization for the micro-structure applying to display devices. As aspects of all-angular coupling optimization, it requires further modification in the actual design.