軟性顯示器光學量測平台之設計與控制

Abstract

近年來，顯示器迅速的發展，從過去陰極射線管(CRT)，經過液 晶顯示器(LCD)的時代，到現在逐漸朝向超薄化的世代邁進。如今， 像紙張一樣輕薄的顯示器已經問世，為人類的生活帶來很大的衝擊。 顯示器具有如紙張般厚度且可撓曲的特性，也因此帶來不少的便利。 本研究針對這種可撓曲的特性進行光學方面的檢測，利用開發的撓曲 平台，使基板產生不同的撓曲半徑，對試片作量測。在量測過程中， 使用CCD 相機擷取軟性顯示撓曲時的弧型輪廓，再對擷取的影像作 前置處理，將影像去除雜訊，接著以模糊強化增強影像對比等方式， 保留所需要的影像，做軌跡的擬合，再使用可以做三種直線運動，及 兩種旋轉運動的五軸移動平台，沿著曲線的方向，掃描檢測基板光學 性質的變化，以單調光源之照度檢測為主。在五軸移動平台中所使用 的控制方法為模糊控制，在此控制方法中加入了基因演算法，以便調 整模糊控制器的比例常數，這些常數包含了誤差、誤差變化量、模糊 控制器輸出之常數；此演算法不斷的藉由計算適應性函數數值的高低 判斷參數的優劣，決定這些參數的選擇與淘汰，以此縮短移動平台的 上升時間、安定時間，並能有效的降低平台超越量與低射現象的問 題。將上升時間後之響應轉換到頻譜觀察，其平台的振動量，比加入 控制器前降低了不少。在軟電基板的照度實驗中，觀察到軟電基板中 心部位，在受到彎矩作用下，撓曲的半徑越大時，所呈現的照度值會 越高。

In recent years, the display has been developed quickly from the traditional cathode ray tube to the liquid crystal display. Nowadays the liquid crystal display is approaching the generation of flexible display. Therefore, the display as thin as papers will be presented to the public with great impact on our life. This display having the property of flexibility makes people’s life more convenient. Hence, this research concentrates on controlling a platform so as to bend the flexible display with different curvature radii to measure mechanical and optical properties during bending of the flexible display. We carry out image preprocessing in the image-processing technique to filter the noise, and to enhance the image contrast using fuzzy techniques and other methods. We scan and detect optical variation along a curve direction to measure the illuminance of monochromatic light. For ease of measurement, the platform can undergo five-axis motion, namely three translations and two rotations. The platform motor is controlled by using a fuzzy controller, associated with a genetic algorithm. The genetic algorithm adjusts parameters of error constant, error change constant, and output constant.The genetic algorithm keeps selecting better parameters based on fitness functions. The platform obtains good performance such as rise time, and settling time. It is effective in decreasing overshoot and undershoot of platform. This study transformed the platform time response platform after the rising time to frequency spectrums. They show that the vibration of platform has been reduced compared with no controller. In the illuminance experiment, we observed the center of the flexible display has higher illuminance with larger curvature radii in bending.