目前液晶電視所採用之背光源幾乎均採用於冷陰極螢光燈管作為背光源，然而隨著液晶電視尺寸之變大，其背光源成本亦隨之增加，此外由於燈管含汞量的環保問題考慮，因此最近亦衍生出新型的外部電極螢光燈管被光模組。此種外部電極螢光燈管背光源的特點便是其含汞量較少，可降低對環境影響；此外，不像於冷陰極螢光燈管需要一對一的反流器驅動，外部電極螢光燈管可用一個反流器驅動多燈管，可有效降低背光源成本，因此本論文選擇此外部電極螢光燈管背光源系統作為研究對象。

本論文之主要貢獻有四：第一點，不需額外增加均流電容器，而是直接利用外部電極螢光燈管本身等效的電容值參與電路的諧振，這樣一來可以減少不必要的被動元件。第二點，吾人提供一個簡易的調光電路，適時的調整功率開關切換之時序，可獲得外部電極螢光燈管調光功能。第三點，冷陰極燈管驅動燈管數與反流器數目成正比，而外部電極螢光燈管可以並聯多根驅動只需一個反流器，吾人以 根燈管作為一個模組配合一個反流器，可以降低成本並提升 左右之轉換效率。第四點，製作出新型多燈管外部電極螢光燈管驅動系統雛形，以驗證其可行性。

Due to the environmental and cost considerations, application of cold cathode fluorescent lamps (CCFLs) as the backlight system is now replacing with novel external electrode fluorescent lamps (EEFLs) backlight system for large-sized LCD TV. In fact this is also the motivation of conducting this research.

Basically, the contributions of this thesis can be summarized follows. First, the inherent uniform equivalent capacitance of the EEFLs are fully used for the proposed full bridge resonant inverter to provide a uniform current sharing capability for the backlight of the large sized LCD TV. Second, the thesis provides a simple dimming-circuit‚ which modulates the sequences of power switches, for acquiring the dimming feature of EEFLs. Third, in order to reduce the inverter rating and increase the efficiency, an inductor is added to the secondary winding of the transformer for reactive power compensation. Due to the large number of EEFLs‚ say ten in this thesis, the efficiency is increased about 10% approximately. Finally, a prototype system is constructed to verify feasibility of the proposed backlight system.

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