多頻譜LED照明系統相較於傳統照明光源的優勢在於它可以透過調光的方式在不同的場合營造出使用者需要的照明環境。然而LED光源在長時間電流的驅動下，往往受其電與熱特性的影響導致光功率下降甚至光源衰變程度不一而產生色偏的困擾。為了能夠偵測光源色偏的問題，光譜儀是一個非常精確的測色儀器能夠直接偵測頻譜的變化，但是考量其價格與普遍性的問題，此設備並非是較好的選擇。因此，本論文採用兩顆RGB色彩感測器作為內部光源與外部環境光感知色彩的裝置，透過色彩校正，能夠在此範圍內不同照度的條件下達到∆u’v’平均小於0.0015，平均照度誤差小於10lux，以用來感測光源色偏現象。而當光源輸出不符理想時，我們透過閉迴路控制的方式進行光源的補償，其結果顯示色彩或是照度偏差達一定誤差時，系統能夠自動地進行調節且有效地維持光源輸出，在三種測試光源的設定上照度誤差為2.2lux/5.6lux/5.3lux，色溫誤差也僅只有5.9K/12.2K/11.9K。
在環境光感測部分，我們透過收集4種光源類別共計24款照明條件對於色彩感測器的特性進行分類，進而發展出決策樹，建立不同環境光源下的校正矩陣，以利色彩感測器判斷室內環境中的照明條件。我們進一步提出兩種多頻譜LED照明的補光與應用模式，一種會隨著環境光色做照度調節，此作法能達到節能的目的；而另一種則是混和環境光在特定的區域達到使用者的需求。在誤差計算後，第一種模式Du’v’小於0.0015，DY僅有0.77%，在另一種模式下Du’v’為0.0017，DY則是2.9%。其結果顯示能有效應用在兩種應用情境中。

The key point enabling multi-spectral LED lighting to be superior to the traditional lighting source is that multi-spectral LED lighting could create a suitable lighting environment by dimming for users in different occasions. However, under the long-term current driven, the effects of electricity and heat from LED Lighting would reduce optical power output and even lead to inconsistent light source decay, which results in color difference. In order to detect color difference of light source, spectrometer, a considerably accurate color detecting instrument, could identify changes in spectrum. Yet, in light of price and universality of spectrometer, the instrument is not a better choice. Therefore, the thesis utilizes two RGB color sensors as the device to perceive interior light source and ambient light. After color calibration, the sensor could get average ∆u’v’ less than 0.0015 and average illuminance error less than 10lux under various illuminance within the range of common mixed temperature (2000K-7000K) to detect color deviation of light.
As the outcome of light source is beyond expectation, we would compensate light source via closed-loop control. The result implies that as differences of color or illuminance have reached certain errors, system can adjust automatically and keep producing light source output effectively. Moreover, by utilizing the way of control, measuring under warm, neutral and cool color temperatures could obtain illuminance errors with 2.2lux/5.6lux/5.3lux respectively and errors of color temperature only with 5.9K/12.2K and 11.9K.
In terms of ambient detection, we classify characteristics of color sensor through collecting four kinds of light source with total twenty-four lighting conditions, thereby generating decision tree. Applying varied light sources chosen by decision tree into calibration matrix, color sensor could recognize lighting condition of interior environment. We, further, propose two modes where light supplement of multi-spectral LED lighting is applied. One of the modes could adjust illumination as color of ambient light alters, which can achieve the purpose of saving energy. The other could meet users’ demands by mingling ambient light in specific area. After calculating differences, the Du’v’ under the first mode is less than 0.0015 and DY is only 0.77%. Under the other mode, the Du’v’ is only 0.0017 and DY is merely 2.9%. The outcomes show that light supplement of multi-spectral LED lighting could achieve effective effect when applied into these two modes.

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