• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.415-417
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• 2009

Color stable and efficient two wavelength white organic light emitting diodes (OLEDs) were fabricated using a iridium(III)[bis(4,6-difluorophenyl)-pyridinato-N,$C^2$'] picolinate (FIrpic) as a blue phosphorescent emitter and a bis(1-phenylisoquinolinato-$C^2$,N)iridium (acetylacetonate) ((piq)$_2$Ir(acac)) as a red phosphorescent emitter. The emitting layers consist of two blue emitting layers and one red emitting layer which is between the two blue layers. The device reaches the peak efficiencies of 7.84 % and 10.3 cd/A at 0.6 mA/$cm^2$. Furthermore, there was little change of EL spectra according to current density change in the device.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.184-187
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• 2009

In this paper, we study effect of charge balance on performance of blue phosphorescent organic light emitting diodes (OLEDs). Charge balance determines the location of recombination zone in the OLEDs. By tuning the charge balance in iridium (III) bis[(4,6-difluorophenyl)-pyridinate-N,C2']picolinate (FIrpic) based blue phosphorescent organic light-emitting devices (PHOLEDs) with a high mobility and high triplet energy electron transporting material, we were able to achieve a high current efficiency of 60 cd/A which is a 3X improvement over previous devices with 3,5'-N,N'-dicarbazole-benzene (mCP) host.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.38-41
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• 2009

We demonstrate a new commercial green phosphorescent organic light emitting device (OLED) in a bottom emission device and top emission microcavity. The bottom and top emitting phosphorescent OLEDs (PHOLED$^{TM}$s) had luminance efficiencies of 60cd/A and 137cd/A respectively, at a luminance of 1,000cd/$m^2$. The top emission microcavity was close to 1953 NTSC color requirements with 1931 CIE color coordinates of 0.231, 0.718. A record green PHOLED lifetime of >3,500hrs to LT95 from 4000cd/$m^2$ is demonstrated for the microcavity device.

• 한국표면공학회지
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• 제56권2호
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• pp.152-159
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• 2023

The night visibility of pavement is being considered as a global issue in the field of traffic safety. Although the spreading glass beads on the lane paints has been mainly used to secure night-visibility by utilizing the effect of retroreflection, obvious shortcoming of this method is that retroflection does not occur in the range where the headlights do not reach the glass beads. The use of functional paints including phosphorescent constituents could be a solution for overcoming fore-mentioned problem. SrAl₂O₄ based chemicals have not only good phosphorescent property, but also are chemically stable compared to existing ZnS based materials. However, this chemicals also need the improvement due to slightly reduced luminous effect in time. Herein, we developed novel paints showing enhanced phosphorescent properties by putting rare earth elements such as Eu, Dy and Y into SrAl₂O₄. These prepared phosphorescent pigments have displayed improved properties in terms of durability and long afterglow. For instance, the property of afterglow has been persisted after 5 hours with luminace of 20.6 mcd/m².

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.4125-4128
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• 2011

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.77.1-77.1
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• 2007

• Transactions on Electrical and Electronic Materials
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• 제8권5호
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• pp.218-221
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• 2007

High-efficiency white organic light-emitting diodes(WOLEDs) were fabricated with two emissive layers and an blocking layer was sandwiched between two phosphorescent dopants, bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl) iridium III(FIrpic) as the blue emission and a newly synthesized red phosphorescent material guest, bis(5-acetyl-2-phenylpyridinato-N,C2') acetylacetonate($(acppy)_2Ir(acac)$). This blocking layer prevented a T-T annihilation in a red emissive layer, and balanced with blue and red emission as blocking of hole carriers. The white device showed Commission Internationale d'Eclairage($CIE_{x,y}$) coordinates of (0.317, 0.425) at 22400 $cd/m^2$, a maximum luminance of 27300 $cd/m^2$ at 268 $mA/cm^2$, a maximum luminous efficiency and power efficiency of 26.9 cd/A and 18.6 lm/W.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.60-61
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• 2007

IAZO (indium aluminium zinc oxide) anode films were co-sputtered on glass substrate using a dual target DC magnetron sputtering system. For preparation of IATO films, at constant DC power of IZO (indium zinc oxide) target of 100 W, the DC power of AZO (Aluminum zinc oxide) target was varied from 0 to 100 W. To analyze electrical and optical properties of IAZO anode, Hall measurement examination and UV/V is spectrometer were performed, respectively. In addition, structure of IAZO anode film was examined by X-ray diffraction (XRD) method. Surface smoothness was investigated by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). From co-sputtered IAZO anode, good conductivity($2.32{\times}10^{-4}{\Omega}.cm$) and high transparency(approximately 80%) in the visible range were obtained even at low temperature deposition. Finally, J-V-L characteristics of phosphorescent OLED with IAZO anode were studied by Keithley 2400 and compared with phosphorescent OLED with conventional ITO anode.

• 한국결정성장학회지
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• 제33권1호
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• pp.31-36
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• 2023

반려동물을 키우는 인구가 증가하고 있고 이에 따라 관련 산업의 규모 및 그 범위가 확대되고 있는 실정이다. 반려동물 악세서리에 대한 다양한 디자인, 기능, 재질 등에 대한 요구가 증대되고 있다. 이에 본 연구에서는 축광 안료를 활용한 반려동물 주얼리 디자인 개발을 제안하고자 한다. 축광 안료는 어두운 곳에서도 스스로 빛을 발산하는 장점을 가지고 있기에 이를 보석 형태의 레진으로 제작하고 반려동물을 위한 주얼리 디자인 개발에 적용하여 최종 디자인 방안을 도출하였다.

• 한국화재소방학회논문지
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• 제22권1호
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• pp.29-36
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• 2008

본 연구는 화재시 연기발생 또는 정전이 발생한 경우 계단을 통해 안전하게 피난할 수 있도록 축광재료를 부착한 계단의 피난유도에 관하여 조사하였다. 실험조사는 설계 제작된 계단에 35명(1차 20명, 2차 15명)의 학생이 참여하여 계단의 시인성(visibility), 오르내림의 편리성과 안심감에 대하여 실험을 실시하였다. 실험 조사결과 축광재료를 사용한 계단코는 정전시에도 계단의 단 높이 확인이 가능하여 계단 오르내릴 때 편리하고 안심할 수 있기 때문에 어두운 곳에서 사람이 피난 행동할 때에 매우 효과적이었다. 따라서 계단코와 계단참에 축광재료를 설치하면 정전이 되더라도 평소와 다름없이 피난을 할 수 있을 것으로 판단된다.