發光二極體色溫控制技術及其於色序式微型投影機之應用

Color-Temperature Modulation of RGB LEDs and It’s Application of Color-Sequential Pico-Projectors

邱嘉豪(Chia-hao Chiu)

指導教授 ： 孫文信 ； 伍茂仁

國立中央大學/理學院/光電科學研究所/碩士(2011年)

摘要

本論文使用色彩序列式光源，利用混色公式設計發光二極體的輸出色溫，在其他限制條件下，可以任意調製光源的消耗功率及輸出亮度。
在不同微型微影機的種類應用下，調製光源的重點會有所不同，例如微型投影機裝設在手機中的應用，設計重點在光源消耗之功率不影響手機本身之功能，本論文針對光源設計出低功率消耗模式，設計色溫目標在6500K，量測光源消耗功率為0.77 W，量測光源亮度為42.34 lm，量測色溫值在6530K。另外也對光源設計出高亮度模式，設計色溫目標在6500K，量測光源消耗功率2.53 W，量測光源亮度78.08 lm，量測色溫值在6700K，亮度的量測值和設計值的差距在5%之內，而色溫的量測值和設計值的差距在3%之內。在改良投影機的過程中，不可能一直使用現成光源模組，本實驗室會自行建立新的光源模組，重新排列光源位置，依然能使用相同的調製方式來設計色溫。
本論文建立出調製色溫之程式化平台，此平台可以設計的色溫範圍在4000K到25000K之間，簡化混色公式，使公式中眾多變數以驅動電流代替，不需要再量測驅動電流、亮度和色度座標多項變數，程式化也節省了混色公式在計算反矩陣時耗費的時間。

關鍵字

色序式微型投影機 ； 色溫控制技術 ； 發光二極體

並列摘要

In this thesis, the modulations on LEDs driving current and duration ratio of RGB-LED-array as light source for pico-projector display were proposed. The light source that we use in this study is OSRAM LE ATB S2W.
We perform our light source in consideration of three orientations, power consumption, brightness, and color temperature. Two designs for different projection types, low power-consumption and high brightness, are proposed. Both types are designed to achieve color temperature of 6500K. For a low-power-consumption type, the light source is able to supply 47 lm with color temperature of 6530K at only 0.85-watt power consumption. For high-brightness type, 78.08 lm flux output with color temperature of 6700K is achieved at 2.53 W. Only 5 % difference in brightness and 3 % difference in color temperature between design and measurement.
Furthermore, we program a computation tool to simplify computations of prominent appropriate RGB duration ratio from inputting different objective color temperature and driving current of each LED. It also shows brightness and color space results.

並列關鍵字

white balance ； pico-projector ； CIE 1931 ； lumens ； power consumption ； RGB LED

參考文獻

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