摘要
近年來由於液晶顯示器擁有輕薄的特性故被廣泛地被在生活之中。然而液晶顯示器依然存在一些缺點，如例如染料式彩色濾光對光源有相當大程度的吸收，造成光源使用效率低；液晶顯示器中的元件(如彩色濾光片)成本高，以及不利於大面積製造等的缺點。
為了改善上述的缺點，本研究將以次微米光柵(sub-wavelength grating)的特性應用在分光模組的設計上。本研究中的分光模組大致包含三個部分：導光板、光柵、透鏡陣列。導光板的設計將從外型著手，以提高出光的均勻性為目標；光柵部分將藉由分析不同形狀下，週期、深寬比對繞射效率的影響，取得較佳的繞射效率進而提高光的利用率；最後，透鏡陣列的設計可令不同的色光，聚焦在對應的次畫素上，完成分光。成品的檢驗將以SEM檢驗外形，並以超低輝度分光計量測此分光模組可達到的色域範圍。光柵、透鏡陣列的製作將以微切削、滾壓製作，以達到降低成本及大面積製作的目標。

Abstract
In recent years, liquid crystal displays (LCDs) have been widely used in various applications due to its thin size and light weight. Unfortunately, there are still some defects can be found on LCD, such as light using efficiency in LCD is low due to the absorption of color filter and the cost of color filter is high and not suitable for large area manufacturing.
To solve problems above, the main objective for this study is to design a color separation module which mainly contains three components: light guide, sub-micron grating and lens array. The design of light guide will optimize its shape in order to uniform the light distribution on the top surface of light guide. In the part of sub-micron grating, simulation will be conduct to find better diffraction efficiency under three conditions like: the shape of grating, aspect ratio and the pitches. The main purpose of lens array design is to focus diffraction lights to sub-pixel then compete the color separation. The profile of this prototype will be inspected by SEM and the color gamut of this color separation module will be measured by SpectroRadiometer. The process to making optical films likes sub-micron grating and lens array is by roll-to-roll imprinting process in order to lower cost and has advantage of large area fabrication.

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