• Proceedings of the IEEK Conference
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• 2002.06b
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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.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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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)

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.243-245
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• 2014

To evaluate light-emitting diode (LED) as potential attractants for Bemisia tabaci adults, attractiveness of white and yellow LED traps were investigated in greenhouse. The yellow LED trap showed the most attractive to B. tabaci adults, followed by a similarly attraction to the white LED trap, whereas the control (no light trap) was little attractive to B. tabaci adults. These results suggested that yellow and white LED traps could be used for environment-friendly insect pest control.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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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.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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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.

• Applied Science and Convergence Technology
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• v.23 no.5
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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.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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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.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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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.

• The Korean Journal of Zoology
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• v.2 no.1
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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.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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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.