When multiple cold cathode fluorescent lamps (CCFLs) are set up in a backlight module, parasitic capacitances are inevitably existent between the lamps and the aluminum back-plank. These parasitic capacitances are different from each other in introducing different leakage currents, and in turn cause current imbalance between lamps with undesired unequal brightness of the backlight module. In order to tackle this current imbalance problem, it relies critically upon a balance driving scheme. This thesis adopts the impedance-matching principle for a uniform light output. A detailed analysis and design of the balance circuit is implemented in a direct-type backlight module, which employs a series resonant parallel-loaded inverter with a transformer to generate a high AC voltage to drive multiple lamps. Adding appropriate capacitors on the load resonant circuits helps alleviate the discrepancy among lamp currents. Based on the experimental results, the maximum total current deviation is defined as an index of the current imbalance for multiple lamps system. Accordingly, the minimum impedance ratio can be provided for the designers to achieve balance driving. A prototype of the multi-lamp driving circuit with balance capacitors is designed and built for a backlight module with 16 lamps in a 32-inch liquid crystal display (LCD). Simulation and experimental results demonstrate the effectiveness and feasibility of the current balance scheme.

台灣最早投入TFT LCD是在1991年。發展早期只有兩家小公司，且受困於日本的技術屏障以及經營規模，一直無法有大格局的突破。直到1998年起，由於經濟開始衰退，日本方才開始陸續釋出TFT LCD相關技術，以授權或技轉方式讓技術開始擴散，此時方有多家台灣廠商開始陸續投入TFT LCD這個行業。 經過多年的努力，政府也漸漸開始重視TFT LCD產業，並且在2003年提出「兩兆雙星」五年國家經濟發展計畫，提供各種資源，全力扶植IC與TFT LCD兩項產業，其中TFT LCD被看好是台灣下一個產值破兆的產業，繼晶元代工之後下一個延續國家科技命脈的蓬勃生機。 從早期多數人連什麼是LCD都沒聽過，迄今八年時間，台灣LCD產業已經蓬勃發展，不僅擁有多家世界級大廠，亦成為全球平面顯示器重鎮。2007年也是台灣TFT LCD面板廠自成立以來最賺錢的一年，台灣整體平面顯示器產值首次超越韓國，整體產值並首度破兆，達到1兆2,849億台幣，其中台灣TFT LCD的產值就佔1兆2,149億台幣，佔全球TFT LCD總產值的44.5%。截至2007年為止，台灣本土TFT LCD上下游產業相關廠商共超過九十家，貢獻台灣GDP超過13%。 本文希望以TFT LCD上游材料行業背光模組為例，進行智慧財產與產業調查之工作，試著審視台灣TFT LCD關鍵零組件「背光模組」主要參與者之專利，藉由連結傳統專利分析與產業分析，從中找到能結合產業事實、專利品質和重要性的研究方法與結果，期能為台灣的背光模組行業，甚至是廣義的TFT LCD零組件行業提出一點意見與貢獻。 / Taiwan first engaged in TFT LCD industry in 1991. Only two small companies involved in the early stage; because of technical barriers established by Japan and insufficient economic scale of operation, there had been no breakthrough. Until 1998, the recession began, so that Japanese began to release the TFT LCD-related technologies by licensing or technology transfer, and resulting in the spread of technology. At this stage there are several Taiwanese manufacturers began to actively engage in TFT LCD industry. After years of efforts, the government has gradually begun to pay attention to TFT LCD industry. In 2003 the government put forward the "Two Trillion, Twin Stars" five-year national economic development plan, said plan provides resources to fully support both IC and TFT LCD industry, wherein TFT LCD is deemed next trillion industry, like Foundry, and may continue the lifeline of national science and technology. In the beginning, most people never heard of LCD. After eight years, Taiwan's LCD industry has flourished, not only has a number of world-class factories, but also has become a global center for flat panel displays. 2007 is also the most profitable year for Taiwan TFT LCD panel makers since their establishment. Taiwan's overall output value of flat panel displays exceed Korea for the first time; the overall revenue is about one trillion 2,849 billion Taiwan dollars, wherein Taiwan's TFT LCD accounted for 1 trillion 2,149 million Taiwan dollars, which also accounts for 44.5% share of the global TFT LCD output value. As of 2007, there are over 90 Taiwan companies related to TFT LCD industries, said companies contribute over 13% of GDP in Taiwan. This author wishes to take TFT LCD backlight industry as an example, performing investigation of intellectual property and industrial work, and try to examine the key patents of key players in the industry. The author looks forward to finding a new way to combine traditional patent analysis and industry analysis method, and make some contribution to the industry.