• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.624-627
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• 2004

본 논문은 LCD Backlight로 사용되고 있는 CCFL의 문제점을 해결하기 위해 간단한 구조를 가지는 mercury-free, Xe 평판형 형광램프에 대한 연구를 하였다. 일반적으로, 수은을 포함한 형광램프는 낮은 온도에서의 휘도문제와 상대적으로 긴 점등시간, 수명과 특히, 환경 문제가 있다. 본 논문에는 화학적으로 안정한 불활성 가스인 Xe을 사용함으로써 기존의 백라이트가 가지고 있는 문제점을 해결하였다. 제작된 8인치$(200{\times}156{\times}10mm)$ 램프는 AC 펄스 전압에 의해 높은 균일도, 안정한 방전, 우수한 전기적 및 광학적 특성을 가진다. 또한 본 연구에서, 무수은 Xe 평판형 형광램프의 전극폭에 대한 전기적 및 광학적 실험을 통하여 90[%]의 균일도에서 $7,000[cd/m^2]$의 휘도와 30[lm/W]의 효율을 얻었다.

• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.597-608
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• 1994

This study was conducted to evaluate the relationships between the environmental exposure and biological monitoring among workers exposed to metallic mercury We interviewed each workers to get the medical history including previous hazardous occupational history. We measured the respiration rate and tidal volume of each worker in order to calculate the 8-hour inhaled mercury of workers. And we wafted to evaluate the effect of exposure duration to mercury concentrations in blood and urine as biologic exposure indices of metallic mercury. The regression and correlation analysis were done to the relationships of 8-hour inhaled mercury and mercury in blood and urine. The results were as follows; 1. The subjects were 35 fluorescent lamp manufacturing workers. The mean age of subjects was .24.8 years old, and the mean work careers of workers was 1.19 years. 89% of the total was consisted man. 2. The correlation coefficients between 8-hour inhaled mercury and mercury in blood and urine were higher than that of only considered air mercury concentration. 3. The correlation coefficients of 8-hour inhaled mercury and mercury in blood and urine were above 0.9 in workers who had exposed to mercury more than 1 year 4. The R-square value and -value of regression analysis between the 8-hour inhaled mercury and mercury in blood and urine was also higher in workers who had exposed to mercury over 1 year than in workers who had less than 1 year working experience. The important results of this study were that relationships between the 8hr-inhaled mercury and mercury in blood and urine was very high than that with air mercury concentration only. And the results were very apparent when considering workers 1 year or more. Therefore we concluded that the work career and respiratory volume of each individuals should be considered in evaluation the, results of biological monitoring of workers exposed to metallic mercury.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.2
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• pp.79-83
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• 2008

In this paper, we introduced a LIF measurement method and summarized the theoretical side. When an altered wavelength of laser and electric power, lamp applied electric power, we measured the relative density of the metastable state in mercury after observing a laser induced fluorescence signal of 404.8nm and 546.2nm, and confirmed the horizontal distribution of plasma density in the discharge lamp. Due to this generation, the extinction of atoms in a metastable state occurred through collision, ionization, and excitation between plasma particles. The density and distribution of the metastable state depended on the energy and density of plasma particles, intensely. This highlights the importance of measuring density distribution in plasma electric discharge mechanism study. The results confirmed the resonance phenomenon regarding the energy level of atoms along a wavelength. change, and also confirmed that the largest fluorescent signal in 436nm, and that the density of atoms in 546.2nm ($6^3S_1{\to}6^3P_2$) were larger than 404.8nm ($6^3S_1{\to}6^3P_2$). According to the increase of lamp applied electric power, plasma density increased, too. When increased with laser electric power, the LIF signal reached a saturation state in more than 2.6mJ. When partial plasma density distribution along a horizontal axis was measured using the laser induced fluorescence method, the density decreased by recombination away from the center.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.12
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• pp.674-678
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• 2013

We present a non-invasive technique to the measure temperature distribution in nano-sized porous thin films by means of the two-color laser-induced fluorescence (2-LIF) of rhodamine B. The fluorescence induced by the green line of a mercury lamp with the makeup of optical filters was measured on two separate color bands. They can be selected for their strong difference in the temperature sensitivity of the fluorescence quantum yield. This technique allows for absolute temperature measurements by determining the relative intensities on two adequate spectral bands of the same dye. To measure temperature fields, Silica (SiO2) nanoporous structure with 1-um thickness was constructed on a cover glass, and fluorescent dye was absorbed into these porous thin films. The calibration curves of the fluorescence intensity versus temperature were measured in a temperature range of $10-60^{\circ}C$, and visualization and measurement of the temperature field were performed by taking the intensity distributions from the specimen for the temperature field.

• Journal of the Korean Vacuum Society
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• v.17 no.6
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• pp.481-486
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• 2008

The different degrees of blackening were observed at the inner surface of borosilicate, soda-lime, and aluminosilicate glass tubes having different sodium (Na) contents. The sodium contents ($Na_2O$) within the borosilicate, soda-lime, and aluminosilicate glass tubes were found to be 4%, 14%, and 0.06%, respectively. The degree of blackening was shown to increase as the sodium content within the glass of the fluorescent lamp containing Ne+Ar+Hg gas mixture. Higher degree of blackening was observed from the inner surface of the glass tube coated with $Y_2O_3$. The blackening was found to be originated from the amalgam of $NaHg_2$ generated by the chemical reaction between the mercury ions within the discharge gas and sodium within the glass tube during operation.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.1
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• pp.11-17
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• 2007

The CCFLs, EEFLs and FFLs use mercury and the operating conditions are different at warm or cold temperature. At start of operation, there may exist a possibility of inhomogeneous operation of lamps or channels of FFL to the very low vapor pressure of mercury at low temperature. In this paper, an inverter with level control block (LCB) was developed to drive LCD backlight using FFL stably at low temperature range. The operation of FFL backlight at $-20^{\circ}C$ was successfully demonstrated by developing inverter with LCB under 130 Watt of power consumption.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.231-234
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• 2009

In order to realize the high luminance and luminous efficacy MFFLs for LCD backlights, we optimized the phosphor profile to enlarge the surface area. The MFFL with the new phosphor profile shows a very wide luminance range from 2,600 to 17,000 nit with the corresponding luminous efficacy from 66 to 32.5 lm/W. The results were obtained with the color coordinate of the phosphor to be around (0.25, 0.23). And the single cell is expanded into a multi-structured configuration to realize a 32 inch-sized lamp by a simple repetition of the single cells, and a new driving scheme is proposed for an adaptive local dimming and scanning drive using dual auxiliary electrodes and bipolar drive scheme. Especially the ultra high luminance and luminous efficacy results suggest the duty time of illumination of the backlight unit can be significantly reduced.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.267-270
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• 2002

The fluoescent lamp has been successfully modeled by employing the radial variation of particle density and considering driving circuit effects on the characteristics of discharge process. The electron energy distribution is assumed to have a Maxwellian. The electron mobility and the ambipolar diffusion coefficients are considered to vary with an electron energy rather than a simple uniform value. Energy states of mercury atom in the discharge process are regarded as six levels rather than simple 4 or 5 levels. These discharge processes have been accurately solved by numerically employing mixed the FDM and the 2nd Runge-Kutta method. This model was applied to analyzing real circuit. Simulation and experimental results were presented to verify the feasibility of the modeling. Simulation and experimental results were presented to verify the feasibility of the modeling.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2075-2078
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• 2005

본 논문은 무수은 평판 형광램프의 구동원리를 해석하기 위하여 주파수 변화에 따른 벽전하와 벽전압 특성이 방전특성에 미치는 영향을 연구하였다. 펄스폭 $9[{\mu}s]$, 300[ns]의 전압 상승 시간을 갖는 펄스파로 방전시켰다. 벽전하, 정전용량, 벽전압의 전기적 특성은 인가된 전압, 전류 파형으로부터 계산하였다. 이때 구동 주파수는 20[kHz]에서 40[kHz]까지 변화시키면서 방전 전후의 정전용량 및 Q-V특성 곡선을 해석하였다. 주파수가 증가하면서 전극간의 정전용량 $C_p$ 방전공간상의 정전용량 $C_o$는 변화를 보이지 않았으나 방전공간과 전극사이의 정전용량 $2C_g$는 증가하는 경향을 보였다. 또한 주파수가 증가하면서 방전개시 전압은 감소하였으며 효율은 감소하는 경향을 보였다.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.5
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• pp.213-217
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• 2005

In this paper, we introduced a LIF measurement method and summarized the theoretical side. When an altered wavelength of laser and electric power, lamp applied electric power, we measured the relative density of the metastable state in mercury after observing a laser induced fluorescence signal of 404.8nm and 546.2nm, and confirmed the horizontal distribution of plasma density in the discharge lamp. Due to this generation, the extinction of atoms in a metastable state occurred through collision, ionization, and excitation between plasma particles. The density and distribution of the metastable state depended on the energy and density of plasma particles, intensely This highlights the importance of measuring density distribution in plasma electric discharge mechanism study The results confirmed the resonance phenomenon regarding the energy level of atoms along a wavelength change, and also confirmed that the largest fluorescent signal in 436nm, and that the density of atoms in 546.2nm ($6^3S_1 {\to} 6^3P_2$ ) were larger than 404.8nm ($6^3S_1 {\to} 6^3P_1$). According to the increase of lamp applied electric power, plasma density increased, too. When increased with laser electric power, the LIF signal reached a saturation state in more than 2.6mJ. When partial plasma density distribution along a horizontal axis was measured using the laser induced fluorescence method, the density decreased by recombination away from the center.