LED (lighting emitting diode, LED)用途廣泛，其陣列(array)更具商業價值，可作為面板背光源、一般照明及車頭燈等應用。唯其照明效果及壽命，受晶片接面溫度高低影響甚鉅，故建立一準確有效之LED陣列構裝熱傳及光學分析方法，以掌握其出光及散熱效能，極為重要。
本論文首先以有限單元分析軟體ANSYS®，建立包含熱傳導、熱對流與熱輻射之三維有限單元熱傳分析模型，以計算LED陣列構裝之溫度分佈。為準確獲得發熱功率，本論文並利用積分球量測輸入LED陣列構裝功率中轉換為光能之部分。本論文接著利用光學軟體lighttool®分析光線於構裝內部不均勻漫射對出光效率及散熱效果產生之影響。
於自然對流下，本論文並以紅外線熱像儀(infrared thermometer，IR)量測LED 陣列構裝表面溫度場，進而探討LED陣列構裝透明模封材料表面是否塗敷黑漆之差異，以獲得模封材料表面正確之表面放射率(emissivity)，並以熱電偶量測驗證及以紅外線熱像儀拍攝、校正後之LED陣列構裝之表面溫度場。此外，為準確求得晶片接面溫度，本論文亦進行了LED構裝內晶片溫度敏感(temperature sensitive parameters, TSP)曲線之量測。上述三維有限單元熱傳分析模型結果經與各項實驗量測結果相比較，顯示此分析模型之準確性。
於確立LED陣列構裝之熱傳與光學分析模型後，本論文最後以較佳之LED陣列構裝散熱陣列擺置為對象，針對不同模封材料外型，建立其流明(lumens)度之回應表面 (response surface)，進而以最適化法(optimization)求解在特定觀察面上出光及亮度最佳之表面，以有效獲得LED陣列構裝最佳之散熱與出光設計。

LED (lighting emitting diode, LED) has been widely used. Its array package specially has high commercial value and can allow various applications to liquid crystal display (LCD) backlight source, general lighting, and automobile instrument, etc.. However, the LED’s illumination performance and lifetime depend on the chip junction temperature distinctly. Thus, to control the thermal and extraction efficiency, the development of an effective thermal and optical analysis method on LED array package is extremely imperative.
Based on the ANSYS® finite element analysis program, this work first establishes a rigorous three-dimensional finite element heat transfer model for the computation of temperature fired of the LED array package, concerning heat conduction, convection and radiation conditions. To get the accurate power of heat, an integrating sphere is adopted to measure the part of photon energy transformed from the input power. Also, this work uses the optical analysis program lighttool® to analyze the influence of nonuniform rays diffusing inside the package thermal and extraction efficiency.
Under natural convection condition, this work uses the IR (infrared thermometer) to measure the temperature distribution on the surface of the LED array package. To obtain the correct surface emissivity of epoxy the difference with optical glass surface painted or not is investigated. The temperature of LED array package which has been measured and calibrated is also verified by thermal couple measurement by IR. In addition, to accurately obtain the chip junction temperature, the temperature sensitive parameter (TSP) curve of the LED array package is also established. To demonstrate the accuracy of the analysis model, computed results obtained from the above mentioned three-dimensional finite element heat transfer model are compared with various experimented results.
After verifying the thermal and optical analysis model, this work finally choose a LED array package with better thermal dissipation for analysis. The response surface of lumen for different shapes of modeling component is developed. The best brightness and most uniform extraction of the specific surface is obtained by an optimization scheme. The methodology achieved can be effectively implemented for the best thermal and optical design of LED array package.

摘要 I
誌謝 V
目錄 VI
表目錄 IX
一、導論 1
二、LED出光效率與散熱 7
2.1內部量子出光效率 7
2.2外部構裝出光效率 9
2.3白光LED原理 10
三、LED陣列構裝光學量測與模擬 13
3.1 幾何光學原理 13
3.2 積分球全光通量量測 14
3.3 LED陣列構裝光學模擬 15
四、LED 陣列構裝之三維有限單元熱傳分析 17
4.1 三維有限單元熱傳分析模型 17
4.2 晶片發熱功率 19
4.3 熱傳邊界條件 19
五、LED陣列構裝之溫度量測 21
5.1熱電偶溫度量測 21
5.2紅外線熱像儀量測 22
5.3 二極體TSP曲線量測 26
5.4 晶片接面溫度量測 31
六、最適化之散熱與出光模組 32
6.1 LED陣列模組選擇 32
6.2 回應表面法 32
6.3 序列二次規劃法 35
七、結果與討論 37
7.1 積分球全光通量量測 37
7.2 構裝之效率模擬 38
7.3 三維有限單元熱傳分析 38
7.4 熱電偶量測實驗 41
7.5 紅外線熱像儀溫度場量測 42
7.6 二極體TSP曲線量測 46
7.7 晶片接面溫度量測 47
7.8 較佳散熱之LED陣列模組選擇 47
7.9 最適化模封材料外型 49
八、結論與建議 50
九、參考文獻 52
附圖與附表 56

表目錄
表一、LED 陣列之驅動功率 56
表二、各元件材料之熱傳導係數 57
表三、各主要元件之單元和節點數 58
表四、Ellison(1989)熱對流參數 59
表五、各色光LED之出光效率 60
表六、各色光LED之構裝效率 61
表七、上表面溫度實驗量測與模擬比較 62
表八、ANSYS®模擬與TSP量測得之LED構裝晶片接面溫度比較 63


圖目錄
圖一、食人魚型LED構裝結構示意圖 64
圖二、LED陣列擺放及電路配置示意圖 65
圖三、積分球總光通量量測之實驗架設 66
圖四、整體模型(含PCB板) 67
圖五、熱電偶溫度量測原理 68
圖六、EIA/JESD51-2規範下之實驗架設 69
圖七、TSP曲線量測之實驗架設 70
圖八、LED構裝晶片接面溫度量測電路配置 71
圖九、改變模封材料外型示意圖 72
圖十、觀察面上九個觀察參考點示意圖 73
圖十一、總光通量對輸入功率變化圖 74
圖十二、出光效率對輸入功率曲線圖 75
圖十三、考慮構裝損失為熱能之比較 76
圖十四、熱電偶溫度量測結果 77
圖十五、未點亮各顆溫度TC與IR溫度比較 78
圖十六、以0.344 W點亮R1 之各顆溫度TC與IR溫度比較 79
圖十七、黑漆校正實驗 80
圖十八、平板校正實驗 81
圖十九、平板與LED表面間溫度量測之比較 82
圖二十、以紅外線熱像儀量測得之噴黑漆後LED陣列表面溫度分佈(e=0.95) 83
圖二十一、校正後紅外線熱像儀量測得之噴黑漆後LED陣列表面溫度分佈(e=0.95) 84
圖二十二、以ANSYS分析軟體模擬之LED陣列表面溫度分佈(e=0.95) 84
圖二十三、二極體之輸入電流-溫差關係曲線 85
圖二十四、二極體之輸入電流-順向偏壓關係曲線 86
圖二十五、LED晶片二極體之TSP曲線圖 87
圖二十六、散熱較佳擺置方式 88
圖二十七、擺置方式前後溫度場比較 89
圖二十八、模封材料外型最適化前後比較 90
圖二十九、觀察面上流明度之比較 91

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