• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.44-50
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• 2021

In this paper, we analyze the efficiency of light sources of CCFL and LED monitors. Cold Cathode Fluorescent Lamp (CCFL), which is widely used as a light source for LCD display, supplies a high voltage of 1,200[V] or more when it is initially driven. In addition, a constant normal voltage of 400 ~ 800[V] after lighting, and 3 ~ 6[ mA] is needed for a power circuit that can stabilize the current. Applying a high voltage causes a lot of stress on the inverter and generates a lot of heat in the cold cathode lamp, causing significant damage to the BLU (Back Light Unit), resulting in a burning phenomenon, which causes the screen to output normal colors when outputting the screen. We can not see the yellow output and the screen darkened. Therefore, in order to prevent such a symptom in advance, efficiency can be increased by using a Light Emitting Diode (LED) as the light source of the LCD display instead of a cold cathode fluorescent lamp (CCFL). As a result, it is shown that the LED method outperforms the CCFL method.

• Journal of the Korean Vacuum Society
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• v.14 no.1
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• pp.49-57
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• 2005

The characteristics of current and voltage in a basic discharge experiment are investigated for a cold cathode fluorescent lamp with ballast capacitors attached at both ends of lamp and for a capacitive coupled external electrode fluorescent lamp. In the current-voltage characteristics for a cold cathode fluorescent lamp except ballast capacitors, it is shown that the typical glow discharge with the cathode fall follows after the dark current and Townsend firing discharge. However, in the characteristics for a cold cathode fluorescent lamp including ballast capacitors, the current increases as the voltage increases in the glow discharge region without representing a cathode fall since the most voltage is loaded at two capacitors. The characteristics for the external electrode fluorescent lamp shows the same as that of the cold cathode fluorescent lamp in the respect of glow discharge characters, and the external electrode itself roles the ballast capacitor.

• Proceedings of the KIPE Conference
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• 1999.07a
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• pp.435-438
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• 1999

Nowadays, the inverter for CCFL(Cold-Cathode Fluorescent Lamp) driver is needed as form of compact size, low loss and high efficiency. This paper deals with comparison of characteristics of the electromagnetic push-pull type inverter and the piezoelectric half-bridge inverter for a CCFL driver. From the experimental results, the piezoelectric inverter is proven as more efficient than conventional electromagnetic inverter.

• Proceedings of the Korean Reliability Society Conference
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• 2005.06a
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• pp.281-286
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• 2005

휘도(Luminance)는 냉음극 형광램프(Cold Cathode Fluorescent Lamp : CCFL)의 신뢰성을 평가하는데 있어 중요한 항목으로 사용되고 있다. 본 연구에서는 휘도 측정시 주위 온도 및 습도에 따라 측정감이 어떻게 변화하는가를 일반화 선형모형(Generalize Linear Model)을 이용하여 알아보고, 측정시의 환경조건 및 측정 오차에 대한 지침을 제시할 수 있게 된다.

• Information Display
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• v.10 no.6
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• pp.11-15
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• 2009

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1308-1312
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• 2011

CCFL(Cold Cathode Fluorescent Lamp)for BLU of LCD and special lighting has been widely utilized. The removal of oxide film formed on electrode of CCFL in manufacturing process is required. In this pape Plasma treatment was carried out to remove the oxide film. To ensure the optimum process, the analysis of sheet resistance, XRD, AFM and solder test was conducted. A minimum sheet resistance and the maximum percentage of the solder coverage ratio were measured in optimal process conditions such as plasma power consumption 600W and processing time of 70 seconds. As the plasma treatment is confirmed to be due to removal of copper oxide, this process is expected to be used as a treatment of electrode for CCFL.

• The Transactions of the Korean Institute of Power Electronics
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• v.11 no.4
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• pp.371-377
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• 2006

Cold cathode fluorescent lamps (CCFL) show complex characteristics, which make it difficult to drive them in parallel. In this paper, a multi-lamp driving scheme is proposed to drive multiple lamps for LCD back light to reduce output current unbalance. This propose system is composed of parallel CCFLs, series transformers. The driving system adopts only one backlight inverter to drive multi cold cathode fluorescent lamps (CCFL). Moreover the circuit introduces a multi-lamp driving transformer to reduce lamp-current imbalance. The validity of the proposed scheme is confirmed by the simulated and experimental results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.502-505
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• 2002

본 논문에서는 냉음극 형광램프의 구조 및 동작원리를 파악하고 램프의 특성을 알아본다. 램프의 특성에 영향을 주는 요소인 관경, 관길이, 가스압, 전극등을 최적화 하여야 하고 CCFL(cold cathode fluorescent lamp) 의 휘도가 관선류, 주파수, 가스압력, 주위온도에 의한 영향에 따른 전기적 및 광학적인 특성을 분석하고자 한다.

• Proceedings of the KIEE Conference
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• 2008.04c
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• pp.149-151
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• 2008

This paper presents an architecture for driving multiple parallel cold cathode fluorescent lamps (CCFLs) for back lighting applications. The key to the architecture is a proposed capacitive coupling approach for lamp ignition. This system is consist of a flyback converter, a single inverter to drive multiple lamps and conductive floating reflector. The topology is capable of driving a number of parallel lamps with independent accurate lamp, current regulation and improving cost effectiveness with significant reduction in size and weight, compared to typical high frequency ac ballast. Experimental demonstration results for ten of parallel CCFLs with simultaneous ignition.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1503-1505
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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.