• 제목/요약/키워드: Side Emitting

검색결과 115건 처리시간 0.022초

The Study of Luminescence Efficiency by change of OLED's Hole Transport Layer

  • Lee, Jung-Ho
    • International Journal of Precision Engineering and Manufacturing
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    • 제7권2호
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    • pp.52-55
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    • 2006
  • The OLEDs(Organic Light-Emitting Diodes) structure organizes the bottom layer using glass, ITO(indium thin oxide), hole injection layer, hole transport layer, emitting material layer, electron transport layer, electron injection layer and cathode using metal. OLED has various advantages. OLEDs research has been divided into structural side and emitting material side. The amount of emitting light and luminescence efficiency has been improved by continuing effort for emitting material layer. The emitting light mechanism of OLEDs consists of electrons and holes injected from cathode and anode recombination in emitting material layer. The mobilities of injected electrons and holes are different. The mobility of holes is faster than that of electrons. In order to get high luminescence efficiency by recombine electrons and holes, the balance of their mobility must be set. The more complex thin film structure of OLED becomes, the more understanding about physical phenomenon in each interface is needed. This paper observed what the thickness change of hole transport layer has an affection through the below experiments. Moreover, this paper uses numerical analysis about carrier transport layer thickness change on the basis of these experimental results that agree with simulation results.

Recent Progress in Alpha-emitting Radiopharmaceutical Development for Clinical Application

  • Choong Mo Kang;Yearn Seong Choe
    • 대한방사성의약품학회지
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    • 제8권2호
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    • pp.157-166
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    • 2022
  • Targeted alpha therapy began to be applied to the treatment of late-stage cancer patients because of its dramatic therapeutic efficacy in patients who have no responses with beta-emitting radiopharmaceuticals. However, its strong cytotoxicity may cause side effects due to undesirable uptake in non-target tissues. In order to use alpha-emitting radiopharmaceuticals for early-stage patients as well as late-stage cancer patients, therefore, modifications on their chemical structures are required. In this review, the recent progress in the development of alpha-emitting radiopharmaceuticals is discussed.

Solution Processable P-OLED (Polymer Organic Light Emitting Diode) Display Technology.

  • Lee, Jueng-Gil;Carter, Julian
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1050-1055
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    • 2005
  • We report the development frontiers that are dictating the speed of adoption of polymer organic light emitting diode (P-OLED) technology in market applications. Our presentation includes both the developments taking place in materials and the rapid advances in the manufacturing processes used for solution processable P OLEDs. On the manufacturing side, the latest progress in ink jet printing process is discussed. On the materials side, we look at both fluorescent and phosphorescent material performance including the CDT development roadmap.

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Solution Processable P-OLED (Polymer Organic Light Emitting Diode) Display Technology.

  • Lee, Jueng-Gil;Carter, Julian
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1355-1360
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    • 2005
  • We report the development frontiers that are dictating the speed of adoption of polymer organic light emitting diode (P-OLED) technology in market applications. Our presentation includes both the developments taking place in materials and the rapid advances in the manufacturing processes used for solution processable P-OLEDs. On the manufacturing side, the latest progress in ink jet printing process is discussed. On the materials side, we look at both fluorescent and phosphorescent material performance including the CDT development roadmap.

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질화계 발광다이오드의 측면 형상화를 이용한 광 추출 효율 향상 (Improvement of Light Extraction Efficiency by Side Surface Texturing in Nitride-based Light-Emitting Diodes)

  • 장동현;심종인
    • 한국광학회:학술대회논문집
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    • 한국광학회 2008년도 동계학술발표회 논문집
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    • pp.95-96
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    • 2008
  • We theoretically investigated the influence of side surface texturing on the light extraction efficiency in nitride-based light-emitting diodes (LEDs). The light extraction efficiency was expected as 1.2 times larger in a LED with textured surfaces compared to without ones.

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Poly(3-alkylthiophene) 전계발광소자에 도입된 alkyl side chain의 길이에 따른 발광특성 (Emitting characteristics with alkyl side chain introduced at poly(3-alkylthiophene) electroluminescent devices)

  • 서부완;김주승;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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    • pp.143-146
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    • 2000
  • We studied effects of alkyl($C_nH_{2n+1}$) chain length on characteristics of poly(3-alkylthiophene) electroluminescent diodes. Among the poly(3-alkylthiophene), poly(3-hexylthiophene)(n=6) and poly(3- octyIthiophene)(n=8) were mainly used for the emitting layer of the diode. The result of experiment, the emission intensity of poly(3-alkylthiophene) electroluminescent diodes depends on the alkyl chain length. Strong emission is obtained from a poly(3-alkylthiophene) diodes of long alkyl side chain length. Emission intensities are enhanced by a confinement of carriers on a main chain with a long interchain distance caused by a long alkyl side chain.

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Effect of Ag Capping Layer on the Emission Characteristics of Transparent Organic Light-emitting Devices with Ca/Ag Double-layer Cathodes

  • Lee, Chan-Jae;Moon, Dae-Gyu
    • Transactions on Electrical and Electronic Materials
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    • 제15권1호
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    • pp.45-48
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    • 2014
  • We have investigated the effects of an Ag capping layer on the emission characteristics of transparent organic light-emitting devices with Ca/Ag double-layer cathodes. The thickness of the Ag layer was varied from 10 to 30 nm, whereas the Ca was fixed to be a 10 nm in the Ca/Ag structure. The luminance and current efficiency on the cathode and anode sides are significantly dependent on the Ag thickness. For example, the current efficiency on the anode side increases from 8.4 to 11.7 cd/A, whereas, on the cathode side, it decreases from 3.2 to 0.2 cd/A as the Ag thickness increases from 10 to 30 nm. These changes in emission characteristics were investigated by measuring electroluminescence, transmission, and reflection spectra.

Blue organic light emitting diodes with carbazole based small molecules and color tunning by controlled side group

  • 김용범;안영주;박지호;강민웅;우형석;박종욱
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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    • pp.514-516
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    • 2003
  • We have fabricated an air stable blue emitting organic electroluminescent devices (OLEDs) with a carbazole based emitting molecule, Bis(3-N-ethylcarbazolyl)terephthalidene (BECP). Our device emits strong blue at 472 nm with the luminance efficiency of near 1 lm/W at a voltage and current density of 8 V and 5.7 mA/cm2, respectively, reaching the brightness up to 5000 cd/m2 at 270 mA/cm2. Finally, in order to tune the emission color from blue to green, we have used Bis(3-N-ethylcarbazolyl)cynoterephthalidene (BECCP), a derivative of BECP by adding cyno group in side chain, and compared the electroluminscence (EL) of OLEDS prepared by BECCP to that of BECP based OLEDs.

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질화갈륨계 발광소자 봉지재의 굴절률 및 곡률 변화에 따른 광 출력 특성 연구 (A study of light output characteristics with various refractive indices and geometrical structures of the GaN based light-emitting device encapsulants)

  • 김형진;유진열;강영래;김재필;곽준섭
    • 조명전기설비학회논문지
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    • 제26권7호
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    • pp.1-8
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    • 2012
  • In this paper, we improved the light extraction efficiency by structural change of LEDs on conventional LEDs. We simulated the LEDs light emission as functions of LED side wall angle, various refractive indices the geometrical structures and analyzed the condition improved the light efficiency. We present the results of experimerns and simulations for light output power from LEDs for various refractive indices and the geometrical structures of the LED encapsulants. When the side wall angle range was from 40[$^{\circ}$] to 30[$^{\circ}$], the LED emission increased. LED side wall angle onto LED using the simulation system with a fine tuning of the structure of the LEDs side wall angle is fabricated. Additionally, we changed the side wall angle of LED package with spherical structure and flat structure. The result of spherical structure ray tracting is higher compared with flat structure about 14[%].

Radiation-Laminar Free Convection in a Square Duct with Specular Reflection by Absorbing-Emitting Medium

  • Byun, Ki-Hong;Im, Moon-Hyuk
    • Journal of Mechanical Science and Technology
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    • 제16권10호
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    • pp.1346-1354
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    • 2002
  • The purpose of this work is to study the effects of specularly reflecting wall under the combined radiative and laminar free convective heat transfer in an infinite square duct. An absorbing and emitting gray medium is enclosed by the opaque and diffusely emitting walls. The walls may reflect diffusely or specularly. Boussinesq approximation is used for the buoyancy term. The radiative heat transfer is evaluated using the direct discrete ordinates method. The parameters under considerations are Rayleigh number, conduction to radiation parameter, optical thickness, wall emissivity and reflection mode. The differences caused by the reflection mode on the stream line, and temperature distribution and wall heat fluxes are studied. Some differences are observed for the categories mentioned above if the order of the conduction to radiation parameter is less than order of 10$\^$-3/ fer the range of Rayleigh number studied. The differences at the side wall heat flux distributions are observed as long as the medium is optically thin. As the top wall emissivity decreases, the differences between these two modes are increased. As the optical thickness decreases at the fixed wall emissivity, the differences also increase. The difference of the streamlines or the temperature contours is not as distinct as the side wall heat flux distributions. The specular reflection may alter the fluid motion.