高功率照明用發光二極體之光學設計

Optical Design of High Power Light Emitting Diode for Illumination

彭柏翰(Bo-Hen Peng)

指導教授 ： 蕭德瑛

國立清華大學/工學院/動力機械工程學系/碩士(2008年)

摘要

本研究針對高功率LED封裝結構之光學透鏡做設計，發展出一套光學透鏡設計方法。採用簡化的LED封裝型態，以透鏡取代反射杯的方式，設計出能夠均勻發光的直射型HP LED之光學透鏡，藉此來降低眩光的傷害。依照所規劃光線路徑建構光線路徑模型，用此模型計算描述輪廓的點資訊。先以參數式描述第一條光線的位置點，計算出位置點相對應的切線向量，再推算其餘光線的點資訊，進而得到完整的透鏡輪廓資訊。接著再透過直線或曲線繪圖透鏡二維輪廓，將輪廓沿著中央軸方向迴轉得到三維實體模型，此模型就可以放入光學軟體中進行模擬與驗證。本研究透過改變透鏡與光源的比例大小，來修正光線路徑模型使用點光源進行分析所產生的誤差，找出透鏡與光源的比例的關係式，得到最佳的透鏡大小。最後利用光強度分析，將透鏡輪廓進行微調，改善在觀察面上的光圖案之照度均勻性，完成整個光學透鏡的設計。

關鍵字

發光二極體 ； 透鏡

並列摘要

In this study, an optical design of the high power light emitting diode (HP LED) for illumination is proposed. A simplified structure of the LED that can use the lens to replace the reflector cup is designed. Therefore, the fabrication cost can be reduced. According to this design concept, a design method of the optical lens is developed. Based on the proposed method, an optical lens of the front-emitting HP LED to obtain a uniform illumination, and reduce the injured of the glare is designed. An optical model is used to obtain the overall point data of the lens profile by mathematics and geometrical optics base on the optical requirement. Either the straight lines or curves are used to draw the lens profile, and then rotate around the central axle to create the 3D optical model. In addition, the several lenses with same form but different scale are analyzed to find the optical properties of each lens in order to select a suitable size of the lens. The emission pattern of the lens is used to adjust the lens profile and each lens profile is analyzed to search the optimization lens profile by the uniformity of the illumination. Finally, an optical lens model with excellent illumination uniformity is found.

並列關鍵字

LED ； Lens

參考文獻

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