• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.646-648
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• 2003

The electrical and optical characteristics of the cold cathode fluorescent lamps (CCFL) were measured and investigated under the wide ambient temperatures ranging from $-30^{\circ}C$ up to $+100^{\circ}C$. The highest luminous efficiency of the CCFL of 55 lm/W was obtained at the ambient temperature of $50^{\circ}C$.

• 한국콘텐츠학회논문지
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• 제21권6호
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• pp.44-50
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• 2021

본 논문은 최적의 모니터 효율성을 설계하기 위해 CCFL과 LED 모니터의 광효율을 비교 분석한다. LCD 디스플레이 광원으로 많이 사용이 되고 있는 냉음극관 램프(Cold Cathode Fluorescent Lamp, CCFL)은 초기 구동 시 1,200[V]이상의 고전압과 점등 후 400 ~ 800[V]의 일정한 정상전압을 공급한다. 또한 3 ~ 6[mA]의 전류를 안정화 시킬 수 있는 전원회로가 필요하다. 고전압을 인가를 하게 되면 인버터에 무리가 많이 가고 냉음극관 램프에 많은 열이 발생을 하여 BLU(Back Light Unit)에 상당한 손상을 주어 그을리는 현상 발생, 이로 인하여 화면 출력 시 화면이 정상적인 색상을 출력을 못하고 노란색 출력, 화면 어두워짐을 확인할 수 있었다. 이러한 증상을 미연에 방지를 하고자 LCD디스플레이의 광원을 냉음극관 램프(Cold Cathode Fluorescent Lamp, CCFL)를 대신하여 발광다이오드(Light Emitting Diode, LED)을 이용하면 효율을 증대할 수 있다. 결론적으로 CCFL 방식보다 LED방식의 효율이 좋다는 것을 증명한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.197-199
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• 2005

The Cold cathode fluorescent lamp (CCFL) are widely used to illuminate the liquid crystal display(LCD). Ballasts are required for CCFL because the lamp need high starting voltage and behave negative dynamic resistant characteristics in the desired region of operation. Dimming methods of CCFL are used to pulse frequency modulation(PFM) or pulse width modulation(PWM). In this paper, CCFL driving and control circuit is designed by half-bridge type series and parallel resonant inverter that variable frequency modulation method to control the output voltage current. The validity of this study is confirmed from the simulation and experimental results.

• 마이크로전자및패키징학회지
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• 제11권2호
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• pp.37-41
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• 2004

LCD TV의 백라이트로서는 cold cathode flourescent lamp (CCFL)를 병렬로 구성한 직하방식의 백라이트 많이 사용되고 있다. 현재 각 각의 CCFL에 transformer 한개 씩을 사용하여 일정한 전류를 공급함으로서 백라이트의 균일도를 얻고 있으나 본 논문에서는 differential driving inverter를 이용하여 transfomer에 8개의 램프를 연결하여 구동함으로써 transformer의 개수를 현저히 줄일 수 있었다. Differential driving 방법을 이용하여 transformer 2개를 사용한 인버터를 제작하였으며 이를 이용하여 길이 450mm, 관경 4mm의 CCFL 16개를 사용한 26"용 LCD TV 백라이트를 구동할 수 있었다. 개발된 differential driving 인버터를 이용하여 백라이트를 구동한 결과 $88\%$ 이상의 휘도 균일도를 갖는 백라이트를 구현할 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.803-805
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• 2008

For the life estimation of CCFLs in edge-lit LCD modules has been required CCFL blackening test, which is executed in the state of low current and long-time operation under the high temperature condition. We investigated the reason why CCFL blackening happened more easily in the above test conditions and the way how mechanical parts had influence upon CCFL blackening in the edge-lit LCD modules.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.363-366
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• 2007

A new current control technique called Amplitude Shift Modulation (ASM) for cold cathode fluorescent lamps (CCFL) has been developed. This new technique sets and continuously controls the current of each individual CCFL in an LCD backlight lamp array.

• Journal of Welding and Joining
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• 제27권4호
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• pp.73-78
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• 2009

Characterization of the microweld CCFL electrode for the TFT-LCD backlight unit was carried out in terms of the glass beading heat treatment conditions. We evaluate the weld zone and parent metal of the microweld CCFL electrodes that were exposed to simulated glass beading heat treatment. The CCFL electrode was composed of the cup made with pure Ni, the pin made with pure Mo and the lead wire made with Ni-Mn alloy. Each part of the electrode was assembled together by micro spot welding process and then the assembled electrodes were exposed to simulated glass beading temperatures of $700^{\circ}C,\;750^{\circ}C$ and $800^{\circ}C$. The microstructures of the microweld CCFL electrode were observed by using optical microscope, scanning electron microscope and EDS. Micro-tensile and microhardness test were also carried out. The results indicated that the grain coarsening in the HAZs(heat affected zones) for both the cup-pin weld and pin-lead wire were exhibited and the grain coarsening of the HAZ for the cup and the lead wire was more obvious than the HAZ of the pin. The micro-tensile test revealed that the fracture occurred at the cup-pin weld zone for all test conditions. The fracture surface could be classified into two parts such as pin portion and cup portion including weld nugget. The failure was seemed to be initiated from the boundary between nugget and pin through the weld joint. The result of the microhardness measurement exhibited that the relatively low hardness value, about 105HV was recorded at the HAZ of the cup. This value was about 50% less than that of the original value of the cup. The reduction of the microhardness was considered as the cause of the grain coarsening due to welding process. It was also appeared that there was no change in electric resistance for the standard electrodes and heat treated electrodes.

• 인포메이션 디스플레이
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• 제10권6호
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• pp.11-15
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• 2009

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.123-127
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• 2004

Cold cathode fluorescent lamp (CCFL) has been used as a light source for direct type backlights for LCD monitors or TV. One inverter for one CCFL was necessary for maintaining the lamp current so that many inverters were used to drive as many CCFLs of direct type backlight for LCD TV. An inverter for driving 16 CCFLs was developed to reduce the backlight cost. The length and diameter of CCFL were 450mm and 4mm, respectively. Backlight including 16 CCFLs for 26" LCD TV was assembled by using one inverter. The uniformities of the assembled backlight operated by the conventional inverter and the newly developed inverter were 75% and 88%, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.787-790
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• 2004

The large size and high brightness backlight system for LCD panel inspection equipment was designed, fabricated, and evaluated. The cold cathode fluorescent lamp (CCFL) instead of the hot cathode fluorescent lamp (HCFL) were used as the light source. The inverters for driving multi-lamp CCFL backlight systems were also designed and fabricated. The measured luminance of the fabricated CCFL backlight system was 20,000 cd/$m^2$ and the uniformity of the backlight was 85%. The fabricated backlight system was successfully applied to the LCD panel inspection equipment.