• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.177-180
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• 1999

In this paper, we studied Surface Discharge Type Flat Fluorescent Lamp(FFL) with High Luminance for LCD Backlighting. This lamp is Surface Discharge Type structure with a pair of Sodalime glass, insulator layer, phosphor layer, and Xe gas gap. There are two influences of Electric field on different dielectric thickness. The Electric field difference at the dielectric layer itself enhances minimum value of firing voltage and luminance uniformity. So, we measured the Electric filed at 0.5mm, 1mm gap length and discharge voltage for difference dielectric layer thickness. In experiment result, the thicker dielectric layer has higher firing voltage and lower current.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.165-168
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• 2007

Electrooptic characteristics of Xe-type flat fluorescent lamps (FFL) have been investigated by using a Q-V Lissajous method. It was found that the luminance of the Mgo-coated FFL became more than doubled compared to normal FFLs operated at the same driving voltage, indicating the possibility of the efficacy improvement in the MgO-coated FFLs. Change in the driving condition, in particular, the duty ratio had effects on the electrooptic properties, and it was found that the duty ratio of 50% was the optimum condition from the viewpoints of the efficacy and the lamp voltage.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1275-1281
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• 2007

The discharge phenomena in a flat fluorescent lamp for the backlight unit of liquid crystal displays are simulated by sung a two-dimensional fluid model. The numerical methods for the calculation of plasma dynamics and the radiation transport are introduced for the discharge simulation and for the transmission of the vacuum ultraviolet lights. The simulation results are presented to compare the luminance and the luminance efficacy with the variation of gas pressure, gas mixture ratio, driving voltage, and frequency.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.147-148
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• 2000

Sealing of two glass plates composing of FED panel was done in a vacuum chamber. Several factors related with a heating process of a frit glass were investigated, including comparisons with a conventional method.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.4
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• pp.161-164
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• 2006

In this thesis we designed the vision system to inspect the defect of a back light unit of plat panel display device. The vision system is divided into hardware and inspection algorithm of defect. Hardware components consist of illumination part, robot-arm controller part and image-acquisition part. Illumination part is made of acrylic panel for light diffusion and five 36W FPL's(Fluorescent Parallel Lamp) and electronic ballast with low frequency harmonics. The CCD(Charge-Coupled Device) camera of image-acquisition part is able to acquire the bright image by the light coming from lamp. The image-acquisition part is composed of CCD camera and frame grabber. The robot-arm controller part has a role to let the CCD camera move to the desired position. To take inspections of surface images of a flat panel display it can be controlled and located every nook and comer. Images obtained by robot-arm and image-acquisition board are saved on the hard-disk through windows programming and are tested whether there are defects by using the image processing algorithms.

• Journal of Power Electronics
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• v.11 no.1
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• pp.97-104
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• 2011

This paper proposes a new alternating current driving method for highly capacitive loads such as plasma display panels or piezoelectric actuators, etc. In the proposed scheme, a current balance transformer, which has two windings with the same turn-ratio, provides not only a resonance inductance for energy recovery but also a current balance among all of the switching devices of the driver for current stress reduction. The smaller conduction loss than conventional circuits occurs due to the dual conduction paths which are parallel each other in the current balance transformer. Also, the leakage inductances of the transformer are utilized as resonant inductors for energy recovery by the series resonance to the capacitive load. Furthermore, the resonance contributes to the small switching losses of the switching devices by soft-switching operation. To confirm the validity of the proposed circuit, prototype hardware with a 12-inch mercury-free flat fluorescent lamp is implemented. The experimental results are compared with a conventional energy-recovery circuit from the perspective of luminance performances.

• 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.

• Korean Journal of Optics and Photonics
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• v.20 no.6
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• pp.334-338
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• 2009

Recently, with increasing demand for flat-panel display product, methods for large area patterning are required. TIR (total internal reflection) holographic photo-lithography isstudied as one of the methods of large area lithography. In conventional TIR holography, light sources for hologram recording and image reconstruction are coherent beams such as laser beams. If the image is reconstructed with an incoherent light source such a UV lamp, the image noise from the coherence of light will be reduced and the UV lamp will be a better light source for large area exposure. We analyzed the effect of spectral bandwidth and angular bandwidth of the light source in image reconstruction and verified image blurring with experiments. For large area patterning which has micro-scale line width, it is expected that TIR holographic photo lithography by UV lamp will become a low-noise and low-priced technique.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.11
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• pp.1179-1185
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• 1991

Ultrathin Reoxidized Nitrided Oxides were formed by lamp heated rapid thermal annealing in oxyzen at temperatures of $1050^{\circ}C$-$1100^{\circ}C$ for 20, 40 seconds. The electrical characteristics of ultrathin films were evaluated by leakage current breakdown voltage. TDDB. FN tunneling. Nitridation and reoxidition condition dependence of charge trapping properties. i.e.. the flat band voltage shift $({\Delta}V_{FB})$ and the increase of charge-to-breakdown $(Q_{BD})$ induced by a high field stress where studied. As the results of analysis. rapid thermal reoxidation was achieved striking improvement of dielectric integrity, the charge to breakdown was increased and flat band voltage shift was reduced.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.111-113
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• 2007

본 논문에서는 제논 유전체 장벽 방전형 평판형광램프용 Fly-Back방식 전자식 안정기를 설계하였다. 본 전자식 안정기는 Fly-Back방식의 능동형 역률 보상 회로와 인버터회로를 사용하여 기존의 Sine wave의 형태가 아닌 펄스파 형태의 출력을 만드는 고역률, 고신뢰성 전자식 안정기를 제작하였다. 제논 평판형광램프의 점등전압은 고압이 사용되므로 램프 파손의 경우와 무부하의 경우로부터 사고를 방지하기 위해 보호회로를 사용하여 이상전압, 이상전류에 의한 사고를 차단했다.