• Journal of the Korean Graphic Arts Communication Society
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• v.22 no.2
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• pp.123-138
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• 2004

The video phone tube (VPT) of monochrome CRT have utilized home door phone, fish-finder and the rear watch monitors. Phosphor screen formation is made by electrodeposition spin coating and thermal transfer methods etc. Recently, thermal transfer method was developed, as a novel method, to form the phosphor surface for mnonchrom VPT. This method have advantages of simple process, automatization, clean environment, saving raw material and saving running-cost. In this study, it was developed new phosphor of VPT, and tested about phosphor paste properties. An experimental studies of VPT as a new phosphor property and improved VPT's manufacturing process shortening and brightness. As thermal transper method is a paste processing, it is important that rheology of phosphor effects on the formation of phosphor screen. Hence this paper was studied rheology properties of phosphor paste and the formation of phosphor screen had looked most suitable condition. Experimented thermal separation properties of low calcination temperature resin and the result analyzed comparison by TGA. Also, examined calcination properties to reduce remaining binder phosphor.

• Journal of the Korean Graphic Arts Communication Society
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• v.22 no.1
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• pp.53-64
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• 2004

The CRT(cathode ray tube) in oscilloscope consists of an electron gun, horizontal vertical deflection system and a phosphor screen. When the electron beam strikes the phosphor screen, the phosphor generates light. The phosphor screen has formed by CRT precipitation method. But, this method has some defects that are complex process, low yield, much consumption of raw-material, dirty working environment, waste problem, require of high cost. Moreover phosphor for oscilloscope used at present has been imported from Japan. Therefore developments of new phosphor and new method(the screen printing) top form phosphor screen for oscilloscope are required to improve these matters. This study was developed novel method(the screen printing) to form the phosphor screen for oscilloscope used new phosphor. This screen printing method has advantages of simple process, high yield, clean working environment, saving raw material and running-cost.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.243-252
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• 2002

We propose a new concept: that of photonic crystal phosphors (PCPs) for display and phosphor related applications. It is well known that microcavities with dimensions comparable to the emitting wavelength strongly enhance light-matter interactions, resulting in a significant increase in spontaneous emission rate, which can be directly translated into enhancement in phosphor efficiency. In recent simulations we have demonstrated that when a microcavity is formed in a nano-phosphor structure, the luminescence band is modified, and can be made spectrally sharp and tunable by engineering the geometry/material properties of the cavity and the surrounding photonic crystal lattice. New phosphor material structures based on photonic crystals are proposed. Applications to thin film EL phosphors and particle phosphors are discussed. Additionally, economic methods of synthesizing and incorporating PCPs into current display applications are proposed.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1382-1384
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• 1998

Electroluminescence is occurred when phosphor is located in electric field. Object of this research show new type of powder electroluminescent device (PELD) for high brightness compared with conventional PELD. New type of PELD structured as follow ITO/phosphor + dielectric/Silver paste). To investigate optical properties of PELDs, EL spectrum, CIE coordinate system, Brightness of PELDs was measured. The suitable ratio between phosphor and dielectric in new type of PELD was 7:3(phosphor:dielectric). At 200 V 400 Hz, new type of PELD which had ratio of 7:3 was 5700 cd/$m^2$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.7
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• pp.567-574
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• 2013

An optical model is proposed in the white LED using phosphor and LED chip. In this paper a new model that describes the absorption rate and quantum efficiency with increasing the mixing ratio of phosphor in silicone, and the allotment of the phosphor absorption optical power in the several phosphor mixing in the silicone. Single phosphor in silicone from the optical measurement data before and after molding, the solution to get the blue optical power and the phosphor emission optical power is proposed. By these solution the absorption rate and the quantum efficiency was obtained. The model with single phosphor mixing in the silicone the validity was confirmed.

• Transactions on Electrical and Electronic Materials
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• v.13 no.5
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• pp.225-228
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• 2012

In order to synthesize LED phosphor materials, we have applied three novel synthesis techniques, "melt synthesis", "fluidized bed synthesis" and "vapor-solid hybrid synthesis", in contrast with the conventional solid state reaction technique. These synthesis techniques are also a general and powerful tool for rapid screening and improvements of new phosphor materials.

• Journal of the Korean Graphic Arts Communication Society
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• v.20 no.1
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• pp.102-112
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• 2002

Cathode ray tubes (CRT) are the most common electronic display in use in information technology. The CRT consists of an electron gun, electrostatic or magnetic fields to direct the electron beam, and a phosphor screen. When the electron beam strikes the phosphor screen, the phosphor generates light. The phosphor screen has formed by precipitation method, electro-forming and centrifuge method. The high quality product was achieved by electro-forming or centrifuge method. Now applying method is electro-forming used with phosphor and Eh(isopropyl alcohol). Now applying method has been much consumption of raw-material, dirty working environment, dangerous fire and require of high cost. New method to form phosphor surface of monochrome is required to improve this matter. This study was developed novel method to form the phosphor surface by heat-transfer method. This method have advantages of simple process, automatization, clean environment, saving raw material and saving running-cost.

• Journal of the Korean Ceramic Society
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• v.51 no.1
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• pp.25-31
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• 2014

New green phosphor is synthesized by reducing $LiAlO_2:xEu^{3+}$ phosphors in a low pressure $H_2$ atmosphere. The $LiAlO_2:xEu^{3+}$ prepared by a solid state reaction method is reported as red phosphor. The effect of the reduction treatment on the $LiAlO_2:xEu^{3+}$ on the crystalline phase change and photoluminescence (PL) property are characterized. The reduced phosphor had a broad green light spectrum centered at 524 nm. The PL intensity of the reduced phosphor increased to a maximum at the reduction temperature of $1100^{\circ}C$. The PL intensity decreased with a further increase in the reduction temperature. The crystalline phase constituting the reduced phosphor varied with the temperature. A new crystalline phase $Li_2Al_4O_7$ was observed at $1100^{\circ}C$. The origin of the green-light emission is discussed in relation to the crystalline phase change.

• Korean Journal of Materials Research
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• v.27 no.6
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• pp.301-306
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• 2017

The discovery of new luminescent materials for use in light-emitting diodes(LEDs) has been of great interest, since LED-based solid state lighting applications are attracting a lot of attention in the energy saving and environmental fields. Recent research trends have centered on the discovery of new luminescent materials rather than on fine changes in well-known luminescent materials. In a sense, the novelty of our study beyond simple modification or improvement of existing phosphors. A good strategy for the discovery of new fluorescent materials is to introduce activators that are appropriate for conventional inorganic compounds, that have well-defined structures in the crystal structure database, but have not been considered as phosphor hosts. Another strategy is to discover new host compounds with structures that cannot be found in any existing databases. We have pursued these two strategies at the same time using composite search technology with particle swarm optimization(PSO). In this study, using PSO, we have tracked down a search space composed of Sr-Al-Si-O-N and have discovered a new phosphor structure with yellow luminescence; this material is a potential candidate for UV-LED applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.581-584
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• 2002

A new method for the preparation of lanthanide ions activated strontium aluminates phosphor by combustion method has been proposed. Combustion method consist of the redox reactions between the respective metal nitrates and urea in a preheated funace at $500^{\circ}C$. The luminescence behavior of the phosphor was studied and compared with corresponding phosphor prepared by conventional method. Effect of $Mg^{2+}$ ion concentration in strontium aluminate phosphor was investigated and the maximum luminescence of about $100cd/m^2$ was obtained. This method gave better brightness and small size to the phosphor than made by conventional method.