背光模組導光板微結構設計對光學輝度分佈影響之研究

Study on Microstructure Design of LGP Affecting BLM Brightness Distribution

張政德(Cheng-Der Chang)

指導教授 ： 于劍平

崑山科技大學/工程學院/機械工程研究所/碩士(2005年)

https://doi.org/10.6828/KSU.2005.00068

摘要

目前小尺寸背光模組的設計中，導光板是成本較低且易自行開發的關鍵零組件。本論文主要利用光學模擬軟體做為分析工具，分為兩個方向：(一)導光板入光側V型溝槽結構之光學之模擬與分析；(二)導光板網點結構光學之模擬與分析。本研究著重在導光板之網點與入光側V型溝槽設計上，這些網點與V型溝槽的排列方式與不同形式的設計，可控制光線從導光板的正面射出，使得其光強度分佈得以均勻，並增加輝度。
本研究首先利用田口式L9直交表做實驗分析，得到影響導光板輝度值的主要製程參數及最佳參數組合，接著藉由此主要影響參數，進行全因素實驗，進而了解製程參數對導光板輝度值的影響趨勢及關聯性。
由田口變異數分析得知，影響導光板網點主要參數有網點半徑及中心距離兩項。當網點半徑越大及網點間距越小時，導光板前方之輝度值越高。反之，當網點半徑越小及網點間距越大，導光板後方之輝度值越高。另外，影響導光板入光側V型溝槽主要參數有V型溝槽間距及V型溝槽角度兩項。當V型溝槽間距及V型溝槽角度越大時，LED光源前方之輝度值越高。反之，當V型溝槽間距及V型溝槽角度越小時，則LED光源前方之輝度值越低。最後，利用全因素實驗得知導光板前方之輝度值會隨著網點半徑的增加而增加；而LED光源前方之輝度值會隨著V型溝槽間距的增加而增加。

關鍵字

V型溝槽 ； 導光板 ； 液晶顯示器背光模組 ； 輝度分佈 ； 網點

並列摘要

Light guide plate (LGP) is a key component of lower cost and easier self-development in LCD backlight module (BLM) with small size. In this paper, we use the optical simulation program to analyze the light guide plate of LCD. The exponent includes two important parts. One is optical simulation and analysis of V-Cut micro-structure on the in light side of LGP. And another is optical simulation and analysis of dot pattern micro-structure on LGP. Therefore dot pattern and V-Cut of LGP in this thesis. The arrangement of dot pattern and V-Cut and the pattern of different, control the light emission from the front surface of the light-guide plate so that the distribution of the power intensity on the front surface can be uniform and the brightness of the light-guide plate can be improved.
At first, this research utilizes Taguchi method L9 orthogonal array to obtain those primary parameters affect the brightness of light guide plate. Then the next step conducts full factorial experiments with the primary effective parameters to understand the trend of the effects and relations between the parameters for brightness of light guide plate.
The results of Taguchi method experiment show that dot pattern of light guide plate has two main influencing factors. One is radius of dot pattern, and other is distance between dot patterns. We also find the brightness in front of light guide plate is higher when the dot pattern radius increasing and dot pattern distance decreasing. The brightness in back of light guide plate is higher when the dot pattern radius decreasing and distance between dot patterns increasing. The experiment results of Taguchi method are shown that V-Cut of light guide plate has two main influencing factors. One is V-Cut pitch, and other is V-Cut angle. We also find the brightness in front of LED is higher when the V-Cut pitch and V-Cut angle increasing. The brightness in front of LED is lower when the V-Cut pitch and V-Cut angle decreasing. The results of full factorial experiment are show that the radius of dot pattern increasing induces the brightness in front of light guide plate increasing. And the V-Cut pitch increasing induces the brightness in front of LED increasing.

並列關鍵字

Liquid Crystal Display (LCD) ； brightness distribution ； Light Guide Plate (LGP) ； dot pattern ； V-Cut ； Backlight Module (BLM)

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