• Journal of Information Display
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• 제11권2호
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2218-2220
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• 1999

Plasma Display Panel(PDP) has mirco-cell, so it is difficult to know the physical properties of particles in PDP cell. To know this, we made a cell that is 200 times as large as a general PDP cell. Using this cell, the temperature and the density of electrons have been measured by the fast scanning probe.

• 천문학회보
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• 제38권1호
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• pp.27-27
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• 2013

Development of bolometer array and camera at millimeter and submillimeter wavelengths plays an important role for detecting submillimeter galaxies (SMGs) which appear to be very bright at the submillimeter and millimeter wavelengths. These SMGs, luminous infrared galaxies detected at mm/submm wavelengths seem to be progenitors of present-day massive galaxies and account for their considerable contributions to the light from the early universe and their expected high star formation rates (SFRs) if there is a close link between the SMG phenomena and the star formation activities and the interstellar dust in galaxies is mainly heated by the star light. In this talk, we review assembly of SMGs compiled with observations using the bolometer arrays and cameras and investigate their spectral energy distribution fits including the data at other wavelengths which trace the photometric properties and the red-shift distribution of galaxies. We find that these bright SMGs significantly contribute to the cosmic star formation rate density at red-shifts of 2-3 (about 8 %) for the spatial distribution of these galaxies.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2884-2888
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• 2010

Two red fluorescent DCJTB derivatives (Red 1 and 2) based on modified pyrans were synthesized and their electroluminescent properties were investigated. Multilayered OLEDs were fabricated with the device structure of ITO/NPB (40 nm)/Red 1, 2 or DCJTB (0.5 or 1%): $Alq_3$ (20 nm)/$Alq_3$ (40 nm)/Liq (2 nm)/Al. All devices exhibited efficient red emissions. In particular, a device containing emitter Red 2 as a dopant in the emitting layer, the maximum luminance was $8737\;cd/m^2$ at 12.0 V, the luminous and power efficiencies were 2.31 cd/A and 1.25 lm/W at $20\;mA/cm^2$, respectively. The peak wavelength of the electroluminescence was 638 nm with the CIE (x,y) coordinates of (0.63, 0.36) at 7.0 V.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.830-833
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• 2009

We report the synthesis and electroluminescent properties of new aromatic compounds as emitting materials based on indenopyrazine, such 2,8-bis(3,5-diphenylphenyl)-6,6,12,12-tetraethyl-6,12-dihydrodiindeno[1,2-b:1',2'-e]pyrazine (DPP-EPY) and 2,8-bis(3',5'-diphenylbiphenyl-4-yl)-6,6,12,12-tetraethyl-6,12-dihydrodiindeno[1,2-b:1',2'-e]pyrazine (DPBPEPY). DPP-EPY showed high thermal stability, narrow FWHM of 46 nm, luminous efficiency of 1.04 cd/A at current density of 10 mA/$cm^2$ and CIE coordinate of (0.161, 0.104).

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1300-1302
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• 2009

Transparent $Zn_2SiO_4:Mn^{2+}$ film has been synthesized by spray pyrolysis with various spraying conditions. It illuminates an efficient green emission with the relative emission intensity about 45% under 147nm excitation of a commercial powder phosphor. Additionally, the zinc precursors and additives play a key factor both controlling luminous efficiency and transparency.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.775-778
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• 2009

Novel blue host material, 4,4'-(dinaphthalen-2-yl)-1,1'-binaphthyl (DNBN), was designed and synthesized for OLEDs. In order to test the electroluminescent properties of DNBN, DNBN was used as the host materials for a blue emitter, PCVtPh. The device exhibited deep-blue emission with the CIEx,y coordinates (x=0.15, y=0.08) at 8.0 V, a luminous efficiency of 1.66 cd/A, a power efficiency of 0.77 lm/W and an external quantum efficiency of 2.30 % at 20 mA/$cm^2$, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 전문대학교육위원
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• pp.82-85
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• 2005

Organic EL has been expected to adopt to a new styles of technology that make flat display after Tang & Vanslyke made good electric luminescence device in late 1980s. Their studies based on multi layer structure that consists of emitting layer and carrier transporting layer using proper organic material. In this study, we made multi layer device using $Eu(TTA)_3(phen)$ as a luminescence material by PVD and investigate luminous properties of each device. But oxidization of organic layer by ITO, energy walls in both pole interface, contaminations of ITO surface, importance of protecting membrane, diffusive dimming of light to cathode organic layer, these causes of degradations are common facts of a macromolecule and micromolecule. We think these degradation caused by the impact of heat and electro-chemical factor, bulk effect and interface phenomenon, and raise a question.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 학술대회 논문집 전문대학교육위원
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• pp.110-113
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• 2002

Organic EL has been expected to adopt to a new styles of technology that make flat display after Tang & Vanslyke made good electric luminescence device in late 1980s. Their studies based on multi layer structure that consists of emitting layer and carrier transporting layer using proper organic material. In this study. we made multi layer device using $Eu(TTA)_3(phen)$ as a luminescence material by PVD and investigate luminous properties of each device. But oxidization of organic layer by ITO. energy walls in both pole interface. contaminations of ITO surface, importance of protecting membrane, diffusive dimming of light to cathode organic layer. these causes of degradations are common facts of a macromolecule and micromolecule. We think these degradation caused by the impact of heat and electro-chemical factor, bulk effect and interface phenomenon. and raise a question.

• 전기학회논문지
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• 제64권11호
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• pp.1587-1591
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• 2015

For a higher definition discharge cell, the method of high speed addressing is necessary. In order to modify the surface charges, the liquefied $TiO_2$ or MgO powder is added on MgO layer in front glass and on the phosphor in rear glass in micro barrier discharge. Both the electro-optical properties and the discharge time lag characteristics are measured from 4 inch. test panel, such as the discharge voltage, current, luminance, luminous efficacy and discharge time lag. As the results, the statistic time lag is improved by about 40 %.