• 한국결정성장학회지
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• 제31권5호
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• pp.212-217
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• 2021

Silica sol에 YAG 형광체를 첨가량별로 spin 코팅 후, 코팅막의 blue LED에서 백색광이 발현되는 정도와 표면 및 곡면 코팅용 binder로써, 적용가능성을 확인하였다. SEM, PSA를 통해YAG의 입자 크기는 D₅₀: 9~10 ㎛ 내외이며, XRD를 통해 YAG의 결정구조가 garnet(Y₃Al₅O₁₂), cubic인 것을 확인하였다. 코팅막은 crack이 없고 동시에 silica sol이YAG 형광체를 균질하게 도포된 형상을 보였으며, 첨가량 증가와 비례하게 코팅막 내에서 YAG 첨가량과 두께는 최대 40 ㎛까지 증가하는 추세를 보였다. 그리고 YAG 첨가량이 증가할수록 PL emission intensity 증가와 chromatic locus 곡선 끝 방향으로 색좌표 이동을 확인하였다. Soda-lime 유리기판 표면에 코팅 후, crack이 없으며 YAG 형광체가 균질하게 도포된 코팅성과 코팅막의 백색광 발현특성을 확인할 수 있었고 이는 직접적으로 LED에 다양한 형태의 형광 형상의 구현이 가능하다는 것을 의미한다.

• International journal of advanced smart convergence
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• 제11권2호
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• pp.59-63
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• 2022

In this study, we study of luminescent solar concentrators comprise thick glass with broadband antireflection coating deposited on the top surfaces and inorganic phosphor layers contacted on the bottom surfaces. Solar cells are contacted to the lateral surfaces of the glass. Experimental results show the broadband antireflection coating increased the short-circuit current of the solar cell.

• 한국전기전자재료학회논문지
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• 제26권8호
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• pp.614-619
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• 2013

Recently, remote phosphor is reported for white LED enhancing of phosphor efficiency compared with conventional phosphor-based W-LED. In this study, Remote phosphor was produced by screen printing coating on glass substrate with phosphor contents rated paste and heat treatment. The paste consists of phosphor, lowest softening glass frit and organic binders. Remote phosphor can be well controlled by varying the phosphor content rated paste. After mounting remote phosphor on top of blue LED chip, CCT, CRI, and luminance efficiency were measured. The measurement results showed that CCT, CRI, and luminance efficiency were 6,645, 68, and 1,16l m/W in phosphor 80 wt.% remote phosphor sintered at $600^{\circ}C$.

• 한국재료학회지
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• 제26권1호
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• pp.22-28
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• 2016

In this study, we fabricated high quality color conversion component with green/red phosphor and low melting glass frit. The color conversion component was prepared by placing the green and red phosphor layer on slide glass via screen printing process. The properties of color conversion component could be controlled by changing coating sequence, layer thickness and heat treatment temperature. We discovered that optical properties of color conversion component were generally determined by the lowest layer. On the other hand, the heat treatment temperature also affected to correlated color temperature (CCT) and color rending index (CRI). The color conversion component with a green (lower) - red (upper) layer which was sintered at $550^{\circ}C$ showed the best optical properties: CCT, CRI and luminance efficacy were 3340 K, 78, and 56.5 lm/w, respectively.

• 한국재료학회지
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• 제16권3호
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• pp.145-150
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• 2006

Various colors of light emitting diodes(LED) and four-band white light sources are obtained using a violet LED and various phosphor films. $BaMg_2Al_{16}O_{27}:Eu\;(blue),\;SrGa_2S_4:Eu\;(green),\;and\;Eu(TTA)_3(PTA)$ (red) phosphors are dispersed in poly-vinyl-alcohol aqueous solutions, and phosphor films are prepared by coating the suspensions to PET film. The narrow band emission of $Eu(TTA)_3(PTA)$ phosphor has excellent red luminescent property for four-band white light excited by the violet LED.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1499-1502
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• 2005

Dense $BaMgAl_{10}O_{17}:Eu^{2+}$ phosphor particles with a spherical shape have been synthesized through spray pyrolysis method using basic aluminum nitrate precursor as a spray solution. This $BaMgAl_{10}O_{17}:Eu^{2+}$ particles prepared by the spray pyrolysis have shown the stronger emission intensity compared to the commercially-available $BaMgAl_{10}O_{17}:Eu^{2+}$. However, thermal stability of the BAM:Eu b lue phosphor is very poor due to changing from $Eu^{2+}$ to $Eu^{3+}$ at the thermal process, so brightness of the phosphor decreases. To improve the thermal stability of the dense BAM:Eu phosphor, the spherical BAM:Eu particles were coated with pure $BaMgAl_{10}O_{17}$ layer using the hydrolysis reaction in a solution system. The synthesized powders were characterized by XRD, SEM and PL. On the other hand, the emission properties of the BAM:Eu phosphors coated with $BaMgAl_{10}O_{17}$ layer before and after thermal treatment at $500^{\circ}C$ for 30 min were estimated under VUV excitation. The brightness of the coated phosphor was higher than that of the uncoated phosphor. Also, the coating thickness of BAM layer in the BAM:Eu particles was optimized.

• 한국표면공학회지
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• 제41권4호
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• pp.169-173
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• 2008

The objective of this study is to coat the $SiO_2$ layer uniformly on the ZnS:Cu phosphors by using Sol-Gel method. From results of SEM micrographs observation, XRD and XPS analysis, it could be confirmed that $SiO_2$ layer was relatively well coated on ZnS:Cu particles. $Ag_2S$ was used as a decoding chemical to analyze the dense and uniform coating performance of $SiO_2$ layer on phosphor particles. It could be concluded that phosphors synthesized from our two step replacement method showed strong blue peak comparing to other method and rather weak green peak also. Obtained particle size of phosphors were about 20m diameter. Luminescence properties of the phosphors were examined by photoluminescence spectra at the excitation wavelength of 270 nm.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.727-730
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• 2004

Closed-cell type barrier ribs such as honeycomb, SDR, inverse SDR and waffle types were produced using capillary molding process. Phosphor layers were formed by osmosis coating process on those barrier ribs. Using the rear plate with closed-cell ribs, the luminance and its efficiency was measured. The results demonstrated a significant improvement in efficiency by combining closed-cell type ribs with a new phosphor forming technology

• Korean Chemical Engineering Research
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• 제47권2호
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• pp.150-156
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• 2009

플라즈마 디스플레이 패널(Plasma Display Panel; PDP)이 Liquid Crystal Display(LCD) 등 다른 대형 평면 디스플레이 분야와 경쟁하기 위해선 제품의 다양성과 발광 효율의 향상, 저가격화, 고화질화 등의 기술 발전이 요구된다. 본 논문에서는 우선 기존 PDP용 녹색 형광체의 특성과 문제점, 이를 해결하기 위한 방법에 대해 개괄적으로 논의한다. 또한, 제품의 다양성을 위해 개발 진행 중인 3D-PDP의 원리와 이의 실현을 위한 형광체의 요구 특성에 대해 기술한다. 대표적인 PDP용 녹색 형광체인 $Zn_2SiO_4:Mn$ 형광체가 가진 문제점은 표면의 높은 음전하와 상대적으로 긴 잔광 시간으로 요약된다. 표면의 높은 음전하와 플라즈마의 가혹한 환경에 노출로 인한 열화 현상은 금속 산화물의 코팅을 통해 해결할 수 있음을 알 수 있었으며, 특히 $Al_2O_3$가 코팅되었을 때 가장 큰 효과를 볼 수 있음을 알 수 있었다. 상대적으로 긴 잔광 시간은 Mn 농도를 늘린 $Zn_2SiO_4:Mn$ 형광체를 사용함으로 개선할 수 있고, 부족한 휘도는 $YBO_3:Tb$ 형광체를 혼합하여 사용함으로써 개선할 수 있었다. 아울러 본 연구에서는 $YBO_3:Tb$ 형광체 대신으로 115%의 휘도를 가지는 $(Y,\;Gd)Al_3(BO_3)_4:Tb$ 형광체의 사용이 가능함을 제안하였으며, 3D-PDP에 적용하기에 적합한 1 ms 내외의 잔광 시간을 가지는 $(Mg,\;Zn)Al_2O_4:Mn$ 형광체를 제안하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1356-1359
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• 2007