微透鏡陣列設計於有機發光二極體之顯示器與照明應用

Design of Micro-Lens Array Film in Organic Light-Emitting Diodes for Display and Lighting Applications

吳勝榮(Sheng-Jung Wu)

指導教授 ： 林晃巖

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.00871

摘要

有機發光二極體(OLED)具有反應速度快、色域廣、重量輕、可撓性等特性，被視為下一個世代顯示器與照明裝置。但由於其層狀堆疊的結構，使大部分光線因為全反射而被困在結構中，造成出光效率低落。利用微透鏡陣列薄膜(MLAFs)破壞全反射，增加OLED出光效率是目前常使用的技術之一。
在本論文中，我們分析了圓錐狀微透鏡的底角與高對於出光效率的影響。我們發現當圓錐狀微透鏡的高與其底部半徑相同時，出光效率增益會最好，其中又以底角70°增益最高，為42.16%。我們還根據市面上常見的OLED顯示器規格，加入了black matrix。我們發現加入black matrix後的OLED在貼附微透鏡陣列的效率增益變得不顯著。於是我們在元件內部做微結構，藉由把光線準直減少被black matrix吸收，來提升出光效率增益。
此外，我們在玻璃基板上貼附了半圓球、金字塔、梯形、圓錐的大透鏡(macro-lens)，把基板模態的光最大極限的萃取出來，照明面積比未貼附透鏡大許多。以半圓球大透鏡為例子，效率增益為133.2%，照明面積為未貼附透鏡的32.4倍。貼附不同形狀透鏡後的強度角度分佈也不同，可以根據其分佈特性，應用在不同的照明裝置上。

關鍵字

有機發光二極體 ； 微透鏡陣列 ； 有機發光顯示器 ； 有機發光照明

並列摘要

ABSTRACT
Owing to its fast response time, wide color gamut, light weight and flexible feasibility, organic light-emitting diode (OLED) is considered as the next generation display and lighting devices. However, due to its multi-layered structures and total internal reflection, most of the lights are confined within the OLED structure, limiting the out-coupling efficiency. It is a common method to improve the out-coupling efficiency through destroying total internal reflection by applying micro-lens array films (MLAFs) on OLED.

In this thesis, we analyze the influence of out-coupling efficiency by the base angle and height of conical micro-lens array film (CMLAF). We found that the out-coupling efficiency can be maximum improved when while the height of CMLAF is equal to the radius of CMLAF, among the enhancement ratio can be 42.16% while the base angle is 70°. We also add the black matrix in our simulation model according to the OLED products in the market. We found the enhancement ratio become helpless after adding the black matrix in OLED. To solve the problem that the lights are absorbed by black matrix, we collimate the lights by arranging the internal micro structure in OLED.

Besides, we attaching spherical, pyramidical, trapezoidical and conical macro-lens on the substrate of OLED, then the substrate mode can be out-coupled maximum and the illumination area can also be larger. For example of attaching spherical macro-lens, the enhancement ratio is 133.2% and the illumination area is 32.4 times compared to the bare OLED. There are different angular intensity profiles for different geometries of macro-lens, which can be used for different lighting application.

並列關鍵字

OLED ； micro-lens ； OLED display ； OLED lighting

參考文獻

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