• 제목/요약/키워드: White Light

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Two-Wavelength에 의한 백색 유기 발광 소자 제작 (The fabrication of White Organic Light-Emitting Diodes using Two-Wavelength)

  • 김중연;최성진;조재영;강명구;신선호;주성후;오환술
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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    • pp.25-28
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    • 2002
  • We have been fabricated white organic light emitting diode with two-wavelength ard mixing blue emit in DPVBi (4, 4-bis(2, 2-diphenylvinyl)-1, 1 -biphenyl)layer and yellow emit in rubrene (5, 6, 11, 12-tetraphenylnaphthacene)as emitting layer which are controlled with thickness. This device emits white light emitting in CIE (0.29, 0.33), 1000cd/$m^2$ at DC 18V.

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피코초 레이저 펄스에 의한 백색광 발생 (White-light Continuum Generation by a picosecond laser pulse)

  • 강명균;이승묵;김도석;이범구
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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    • pp.244-245
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    • 2001
  • 강한 펄스 레이저가 렌즈에 의해 투명한 매질 속에 집광되면 가시광선 영역에서부터 적외선 영역에 걸친 넓은 파장대의 빛이 발생하게 되는데 이것을 White-Light Continuum이라고 한다. 이 현상은 1970년에 Alfano 와 Shapiro에 의해 처음으로 발견되었으며 그 후에 여러 투명한 매질들을 통해 White-light continuum의 발생이 확인되었다. 물($H_2O$)과 중수(D$_2$O)에서도 이런 펄스 백색광의 발생이 관찰되어졌으며 고체 매질에 비해 집광된 강한 빛에 의해 생기는 손상에 대한 self-healing이 뛰어나 백색광을 발생시키기 위한 이상적인 매질로 인식도고 있다. (중략)

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온실에 발생하는 담배가루이 성충에 대한 LED 트랩 방제효과 (Efficiency of LED Trap on Controlling Tobacco Whitefly, Bemisia tabaci Adults in Greenhouse)

  • 전주현;이상계;이회선
    • Journal of Applied Biological Chemistry
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    • 제57권3호
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    • pp.243-245
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    • 2014
  • 온실에 발생하는 담배가루이 성충에 대한 LED 트랩의 시설재배지내의 이용 가능성을 평가하기 위해 white LED (450-625 nm) 및 yellow LED (590 nm) 트랩과 광원이 장착되지 않은 트랩을 이용하여 유인활성을 비교하였다. 광원별 일일 포획 밀도 변화는 yellow LED 트랩에서 가장 높은 유인활성을 나타내었으며, white LED 트랩 또한 유사한 개체수가 포획되었다. 그러나 대조구로 사용된 광원이 설치되지 않은 트랩의 경우 광원이 설치된 트랩보다 적은 개체수가 포획되었다. 이러한 결과를 바탕으로 white LED 및 yellow LED 트랩이 시설재배지내에서의 친환경적 해충방제법으로의 가능성을 보여주었다.

White-light-emitting Organic Electroluminescent Device Based On Incomplete Energy Transfer

  • Song, Tae-Joon;Ko, Myung-Soo;Lee, Sung-Soo;Cho, Sung-Min
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.701-705
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    • 2002
  • In order to realize full color display, two approaches were used. The first method is the patterning of red, green, and blue emitters using a selective deposition. Another approach is based on a white-emitting diode, from which the three primary colors could be obtained by micro-patterned color filters. White-light-emitting organic light emitting devices (OLEDs) are attracting much attention recently due to potential applications such as backlights in liquid crystal displays (LCDs) or other illumination purposes. In order for the white OLEDs to be used as backlights in LCDs, the light emission should be bright and have Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.33, 0.33). For obtaining white emission from OLEDs, different colors should be mixed with proper balances even though there are a few different methods for mixing colors. In this study, we will report a white organic electroluminescent device based on an incomplete energy transfer. In which the blue and green emission come from the same layer via incomplete energy transfer.

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$Zn(HPB)_2$와 Zn(HPB)q를 이용한 White OLEDs의 전기적 특성 (Electrical Properties of White OLEDs used such as $Zn(HPB)_2$ and Zn(HPB)q)

  • 장윤기;김병상;김두석;이범종;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.416-417
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    • 2006
  • Organic light emitting diodes (OLEDs) show a lot of advantages for display purposes. Because OLEDs provide white light emission with a high efficiency and stability, it is desirable to apply OLEDs as an illumination light source and back light in LCD displays. We synthesized new emissive materials, namely [2-(2-hydroxyphenyl)benzoxazole] ($Zn(HPB)_2$) and [(2-(2-hydroxyphenyl)benzoxazole)(8-hydoxyquinoline)] (Zn(HPB)q), which have a low molecular compound and thermal stability. We studied white OLEDs using $Zn(HPB)_2$ and Zn(HPB)q. The fundamental structures of the white OLEDs were ITO/PEDOT:PSS (23 nm)/NPB (40 nm)/$Zn(HPB)_2$ (40 nm)/Zn(HPB)q (20 nm)/$Alq_3$ (10 nm)/LiAl (120 nm). As a result, we obtained a maximum luminance of $15325\;cd/m^2$ at a current density of $997\;mA/cm^2$. The CIE(Commission International de l'Eclairage) coordinates are (0.28, 0.35) at an applied voltage of 9.75 V.

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White Light Generation from Single Gallium Oxide Nanoparticles co-doped with Rare-Earth Metals

  • Patil, Prashant;Park, Jinsung;Lee, Seung Yong;Park, Jong-Ku;Cho, So-Hye
    • Applied Science and Convergence Technology
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    • 제23권5호
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    • pp.296-300
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    • 2014
  • The synthesis of pure and rare-earth doped gallium oxide (${\beta}-Ga_2O_3$) nanoparticles is reported. The synthesized nanoparticles are characterized with XRD, TEM, and PL analyses. Strong blue emission is observed from un-doped gallium oxide nanoparticles, while nanoparticles doped with $Eu^{3+}$ and $Tb^{3+}$ give strong red and green emissions, respectively. When doped with $Eu^{3+}$ and $Tb^{3+}$ together, gallium oxide nanoparticles emit white light. The CIE coordinate of the emitted light was found to be (0.33, 0.33), which is well within the white light region.

백색광 간섭계의 위상 정점 알고리즘에서 조명에 따른 위상 정점 모호성에 관한 연구 (Phase Peak Ambiguity According to Illumination in White-Light Phase-Shifting Interferometry)

  • 김기홍;이형석
    • 한국정밀공학회지
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    • 제25권1호
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    • pp.85-91
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    • 2008
  • White light scanning interferometry has gotten a firm position in 3D surface profile measuring field. Recently, the LCD industry gave a chance for this technology to enter into real industry fields. It is known that white-light phase-shifting algorithm give a best resolution compare to other algorithms, but there are some problems to be resolved. One of them is 300nm jump in height profile, called bat-wing effect. The main reason of this problem is an ambiguity of phase-peak detection algorithm, and some solution has been proposed, but it didn't work perfectly. In this paper, I will show the cases when these effects are occurred, and these height discrepancies will be almost disappeared when broad-band illuminators are used.

White Light -Emitting Diodes with Multi-Shell Quantum Dots

  • Kim, Kyung-Nam;Han, Chang-Soo;Jeong, So-Hee
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.92-92
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    • 2010
  • Replacing the existing illumination with solid-state lighting devices, such as light-emitting diodes (LEDs) are expected to reduce energy consumption and environmental pollution as they provide better efficiency and longer lifetimes. Currently, white light emitting diodes are composed of UV or blue LED with down-converting materials such as highly luminescent phosphors White light-emitting diodes (LED) were fabricated with multi-shell nanocrystal quantum dots for enhanced luminance and improved stability over time. Multi-shell quantum dots (QDs) were synthesized through one pot process by using the Successive Ionic Layer Adsorption and Reaction (SILAR) method. As prepared, the multi-shell QD has cubic lattice of zinc-blend structure with semi-spherical shape with quantum yield of higher than 60 % in solution. Further, highly fluorescent multi-shell QD was deposited on the blue LED, which resulted in QD-based white LED with high luminance with excellent color rendering properties.

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가물치 망막중의 시각물질에 관한 연구 (Studies on The Photosensitive Substances in The Kamulchi (Snake Head) Retina)

  • 강성호
    • 한국동물학회지
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    • 제2권1호
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    • pp.11-16
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    • 1959
  • 가물치(Ophice phalus argus)의 안구망막에 존재하는 시각물질을 spectrophotometry 한 결과 다음과 같다. (1) 암순응된 가물치 안구망막에서 2 % digitonin 으로 시각물질을 추출하여 광조사전의 흡광 spectrum을 측정한 결과 흡광 maximum 은 350$\mu\textrm{m}$, 420$\mu\textrm{m}$, 550$\mu\textrm{m}$, 590$\mu\textrm{m}$에 있으며 있었으며 광조사후의 흡광 spectrum과의 difference spectrum 의 흡광 maximum 은 390$\mu\textrm{m}$, 427 $\pm$2$\mu\textrm{m}$, 550$\mu\textrm{m}$, 595$\mu\textrm{m}$에 있었다. (2) 가물치 망막중의 시각물질인 390$\mu\textrm{m}$, 427$\mu\textrm{m}$, 550$\mu\textrm{m}$, 595$\mu\textrm{m}$의 삼원색광에 대한 감광도는 다음과같다. a. 390$\mu\textrm{m}$은 blue light > red light = green light > white light . b.427$\mu\textrm{m}$ 은 red light >blue light > white light > green light c. 550 $\mu\textrm{m}$과 595$\mu\textrm{m}$ 은 blue light > red light > green light > white light (3) 390 $\mu\textrm{m}$ 과 427$\mu\textrm{m}$에서 흡광 spectrum의 maximum을 가지는 시각물질은 그 존재를 예시하던 새로운 색소이다. (4) 가물치의 시각물질은 증류수에도 용출되나 2 % digitonin 수용액으로 추출하였을때보다 명확하지 못하였다. (5) 가물치는 담수어임에도 불구하고 거북류와 같이 visual voilet 는 발견할 수 없었다.

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휴대폰용 소형 Flash에 적합한 LED 램프 설계 연구 (A study on the small Flash Lamp Design using LED)

  • 정학근;정봉만;한수만;박석인;송유진;이정훈
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2007년도 추계학술대회 논문집
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    • pp.107-109
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    • 2007
  • LED is expected as an environmentally friendly light source with its good reliability and long lifetime. A few ten mW white LED can substitute for the indicator light source, and it is required to study several watt multi-chip semiconductor light sources in order to replace the light sources for general illumination such as incandescent lights and fluorescent lamps. Since the optical technology used for several mW white LED light source uses only 30% to 50% of the light, it is required to develop the design technology of optical system and lens to improve the efficiency more than 80% for insuring the high power of white LED. In this paper, we designed and fabricated new structure reflector to increase the efficiency.

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