以基因演算法達成直下式背光模組之三色發光二極體最佳化角度配置

Optimize Placement Angles of RGB LEDs for Direct Type Backlight by Genetic Algorithm

李武原(Wu-Yuan Lee)

指導教授 ： 黃健生

中原大學/工學院/機械工程研究所/碩士(2007年)

https://doi.org/10.6840/cycu200700889

摘要

本文提出一新型錐狀光學透鏡(novel cone-shaped lens)取代低取光率的擴散板(diffuser plate)，改善背光模組(backlight unit, BLU)出光效率，並以基因演算法(genetic algorithm, GA)搜尋最佳的發光二極體(light emitting diode, LED)角度配置，藉此降低BLU色差(color difference)。本研究所設計的lens外側鍍上金屬鏡面(mirror)，將投射到此鏡面的光線導向側邊，避免LED光源之光點(spot)過於集中，進一步將設計的光學透鏡發包製做，並以實驗驗證模擬的準確性。由實驗結果可知，本研究所設計lens能夠有效提升8.9%的取光率。最後透過Matlab與TracePro連結搭配基因演算法，改變LED的擺放角度，尋求最佳化的LED角度配置，使BLU提高取光率，同時擁有最佳的色彩均勻度。本研究所得出模擬結果，在55mm×55mm的背光模組上，可達到85%以上的輝度均勻度，且色差在0.015以下。

關鍵字

背光模組 ； 最佳化 ； 發光二極體 ； 基因演算法

並列摘要

This study proposes a novel cone-shaped lens to replace the low light-efficiency diffuser plate to improve the light output efficiency and simultaneously maintain the satisfactory uniformity. The cone-shaped lens is coated as mirror on the outside surface to reflect the light emitting from the LED below the cone. This reflection leads the light from LED to the side of the optical axis, not along with it, and avoids bright spots on the backlight directly. A prototype of LED backlight module with the designed lens is built to verify the simulation results. In this study, the 8.9% increase in cavity efficiency made possible by the combined use of the novel cone-shaped lens. Finally, perform genetic algorithm through Matlab and TracePro, and search for a set of optimal angle placement of LEDs for color uniformity of BLU optimization. Results of simulation for BLU of 55mm by 55mm, the luminance uniformity that can be more than 85%, and the color difference is under 0.015.

並列關鍵字

genetic algorithm ； optimization ； LED ； BLU

參考文獻

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