摘 要

奈米碳管背光模組(Carbon Nanotube Backlight Unit)，具有高亮度、無汞蒸氣、高色彩飽和度與低表面溫度等特性，為一可以大幅解決冷陰極管諸多缺陷的新型平面光源(Flat Surface Lighting source)，可說甚有機會成為未來大尺寸液晶顯示器主流背光源(Back-Lighting Source)。然而目前其中之奈米碳管背光面板尚有發光效率(Luminescent Efficiency)較低之問題，因此本論文主要之研究乃聚焦於探討奈米碳管背面板之發光特性，同時提出一新型驅動策略以提升其發光效率，最後並完成奈米碳管背光模組所需之閘極驅動電路與陽極高壓直流電源。
　　本論文主要貢獻有四點，第一，針對工研院最新研發之20吋面板結構與螢光粉基礎下，建立一螢光粉發光動態模型等效電路以利後續模擬分析用。第二，利用此螢光粉發光動態模型，可以嘗試各種不同型式之驅動電壓進行模擬，預測其發光情形，進而發展出一更有效利用螢光粉殘光效應之新型驅動策略，對於背光面板發光效率提升效益至為顯著。第三，由於奈米碳管背光模組之場發射電流與閘級驅動電壓呈非線性特性，以本論文製作之雛型為例，採用脈波驅動時，會造成陽極電壓自4kV下降至3.5kV，會影響發光強度，而採用本論文所提之三角波驅動方法，則僅約自4kV下降至3.95kV，大幅改善了脈波驅動造成陽極電壓驟降之缺點。最後第四點，作者並實際製作，完成驅動奈米碳管背光面板所需之雛型電路以驗證所提新型驅動策略之有效性。實測結果顯示本論文所提驅動策略之發光效率較利用目前最佳之脈波驅動方法高出74%。

ABSTRACT

Carbon nanotube backlight unit (CNT-BLU) is one of the categories of flat surface back-lighting source, which have been developed recently. Comparing with cold cathode fluorescent lamp (CCFL) backlight unit, CNT-BLU has the advantages of high brightness, mercury free, superior color performance and low surface temperature etc.. These merits render the CNT-BLU rather attractive as a backlight unit candidate. However, so far, the luminescent efficiency of CNT-BLUs is not good enough. Hence, the major motivation of this research is trying to further increase the luminescent efficiency of CNT-BLUs.
Basically, the major contributions of this thesis may be summarized as follows. First, an asymmetrical dynamic model of the luminescent property of phosphors is first derived. Second, the derived model is then used to investigate various driving voltage waveforms to further improve the luminescent efficiency by simulations. Then, based on the simulation results, a novel driving strategy is proposed to fully exploit the persistence effect of phosphors for a 20-inch CNT-BLU. Finally, a prototype of the proposed driving system is implemented and tasted. Experimental results show that the resulting illuminative efficiency can be increased by more than 74% as compared with the most recent pulse mode driving strategy.

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