• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1116-1119
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• 2008

We developed phosphorescent white OLEDs with high efficiency and color stability. By engineering device architecture in which confined excitons within the emissive layer by using adequate interlayer and balanced recombination of charge carriers by using stepwise hole transporting layer system, these WOLEDs showed power efficacy of 43.6 lm/W with CRI = 62 and 36 lm/W with CRI = 72 at $100\;cd/m^2$ without outcoupling enhancements.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.543-544
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• 2008

In the fabrication of inverted top emission organic light emitting diodes (ITOLEDs), the organic layers are damaged by high-energy plasma sputtering process for transparent top anode. In this study, the plasma process induced damages on metal oxide hole injection layers (HILs) including $WO_3$, $MoO_3$, and $V_2O_5$ as buffer layer are examined. With the result of IV characteristic of hole-only devices, we propose that $MoO_3$ and $V_2O_5$ are stable materials against plasma sputtering process.

• Journal of Information Display
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• v.12 no.4
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• pp.219-222
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• 2011

Iridium-(III)-bis[(4,6-di-fluorophenyl)-pyridinate-N,$C^2$' ]picolinate-based blue phosphorescent organic light-emitting diodes with different electron transport materials were fabricated. Each electron transport material had different electron mobilities and triplet energies. The device with 1,3,5-tri(m-pyrid-3-yl-phenyl)benzene had the highest external quantum efficiency (20.1%) and luminous current efficiency (33.1 cd/A) due to its high electron mobility and triplet energy. The operational stability of each device was also compared with that of the others. The device with 2,2',2"(1,3,5-benzenetriyl)tris-(1-phenyl-1H-benzimidazole) was found to have a longer lifetime than the other devices.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.1149-1152
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• 2003

Now a days, many different kinds of display technologies such as Liquid Crystal Display (LCD), Organic Light Emitting Diode (OLED), and Liquid Crystal On Silicon (LCOS) are designed. And these display technologies will be used in many application products like High Definition Televisions (HDTVs) or mobile devices. In this paper, pattern generation circuit for display test is proposed. The proposed circuit will be embedded in the control circuit of display chip. Two differenct kinds of patterns is generated by the circuit. One is block pattern for color test, and the other is line pattern for pixel test. The shape of test pattern is determined by the values of registers in pattern generation circuit. The circuit is designed using Verilog HDL RTL code.

• Electronics and Telecommunications Trends
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• v.22 no.5
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• pp.46-56
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• 2007

투명전자소자는 투명한 특성을 이용하여 기존의 전자기기가 가지고 있는 공간적/시각적 제약을 해소하려는 목적을 가진 소자이며 투명트랜지스터를 기반으로 한다. 투명 트랜지스터는 투명반도체(주로 산화물), 투명절연체, 투명전도체로 구성되어 있다. 투명 트랜지스터와 투명 OLED를 결합한 투명디스플레이에 정보 인식/정보 처리 기능이 추가로 구현되어 있는 공간 임베디드 정보 단말기를 스마트 창이라고 부른다. 투명전자소자는 초기에는 투명하지 않은 형태의 산화물 트랜지스터를 이용한 디스플레이 분야에 주로 이용될 가능성이 높고 2010년 이후에 투명 IC, 스마트 창 형태의 신규 시장이 창출될 것으로 예측된다. 또한, 투명전자소자 분야는 세계적으로 개발 초기단계이기 때문에 원천 특허 확보 등에 주력할 필요가 있다.

• Vacuum Magazine
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• v.1 no.2
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• pp.19-23
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• 2014

Transparent and top emission organic light-emitting device (OLEDs) are the important issues in realizing new display applications such as see-through electronic displays, and flexible displays. The cathode of the transparent and top emission OLEDs should be transparent in the visible light and should not give any damage to the underlying organic layers, in addition to its intrinsic role of injecting electrons into the organic layers. Several authors have investigated the transparent conducting oxide films prepared by sputtering methods. They have introduced the sophisticated sputtering process for reducing the damages. Other groups have developed thermally evaporated transparent cathodes which are believed to be damage free without causing any permanent defect to the organic layers. This review focuses on the vacuum evaporated damage free transparent cathodes.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.784-787
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• 2002

Oganic light emitting diodes (OLEDs) using PBD(2-(4-biphenylyl)-5-(4-tert-butylpheny)-1,3,4oxadiazole) as a hole blocking layer were fabricated and their device performances were investigated. The devices have a structure of glass substrate ${\setminus}$ indium tin oxide (ITO) ${\setminus}$ TPD(HTL)${\setminus}$PBD,BCP(HBL)${\setminus}$Alq3(EIL)${\setminus}$Mg:Ag(cathode). In this work Bathocuproine(BCP:2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline) and PBD which were previously known as a good ETL material were used as a HBL. By employing HBL, the luminance and quantum efficiency of OLEDs could be improved due to the increase of recombination probability of electrons and holes.

• Journal of Information Display
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• v.10 no.2
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• pp.80-86
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• 2009

The variation of the electrical characteristics of thin-film transistors (TFTs) causes a non-uniform image quality problem, and the differential aging of organic light-emitting diode (OLED) devices causes an image-sticking problem. A video data correction method is proposed herein as an effective solution to the non-uniform electro-optical characteristics of the pixels in activematrix organic light-emitting diode (AMOLED) displays. The results of the simulation that was conducted show that the proposed method successfully senses the electrical characteristics of TFTs and the degradation of OLEDs and effectively compensates for them.

• Journal of Information Display
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• v.11 no.2
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• pp.52-56
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• 2010

High-efficiency organic light-emitting diodes (OLEDs) based on multilayer transparent electrodes (MTEs) are reported. The dielectric/metal/dielectric (DMD) multilayer electrode based on a thin silver layer achieved high sheet conductance as small as $6{\Omega}/sp$ and a tuning capability in the optical and electrical properties by engineering the inner and outer dielectric layers. In the conventional normal bottom-emitting structure, a DMD-based OLED can be fabricated with 90% higher forward luminous efficiency and 30% higher external quantum efficiency (EQE) compared to ITO-based devices. Special attention was paid to the optimization method of such MTE structure considering both the injection and optical structures.

• Transactions on Electrical and Electronic Materials
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• v.6 no.3
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• pp.91-96
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• 2005

We report the efficient red light-emitting diodes based on the fluorescent dye 4-(dicyanomethylene)-2-i-propyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTI) and 5,6,11,12-tetraphenyl naphthacene (rubrene) codoped in the tris(8-hydroxyquinoline)aluminum $(Alq_3)$. Luminance efficiency of 2.2 cd/A with a Commission International De L'Eclairage (CIE) chromaticity coordinate of x, y = (0.640, 0:350) are achieved at the driving current density of $20\;mA/cm^2$. Adding the rubrene to the DCJTI in tris(8-hydroxyquinoline)aluminum $(Alq_3)$, the red color purity and luminance efficiency improved comparing to the DCJTI only doped devices because the rubrene molecules assist the polarization effect of DCJTI by molecular interaction and enhance the energy transfer from $(Alq_3)$ to DCJTI.