• Journal of the Korean Graphic Arts Communication Society
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• v.30 no.1
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• pp.47-58
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• 2012

The inorganic powder EL lamp was made by screen printing technique with a phosphor ink and a dielectric ink. Value of color coordinates X and Y increased under the condition of supplying driving power to the inorganic powder EL lamp and changing voltage with constant frequency. When frequency was changed under the constant voltage, value of color coordinates X and Y were decreased with increasing frequency. However, level of change of color coordinates X was different from color coordinates Y. When voltage was increased under constant frequency, changing degree of color coordinates X and Y shows similarity. But under the constant voltage with changing frequency, color coordinates X and Y were differently changed that degree of change of color coordinates Y showed five times more than that of color coordinates X. As increasing thickness of phosphor ink and dielectric ink, level of voltage and frequency, color coordinates X and Y were slightly changed. According to the thickness of phosphor ink and dielectric ink, and level of voltage and frequency, color coordinate of color light was changed. Frequency was most important element influencing on the change of color coordinate.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.454-459
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• 2013

Recently, remote phosphors have been reported for application to white LEDs to provide enhanced phosphor efficiency compared with conventional phosphor-based white LEDs. In this study, a remote phosphor was produced by coating via screen printing on a glass substrate with different numbers of phosphor coating. The paste consists of phosphor, lowest softening glass frits, and organic binders. The remote phosphor could be well controlled by varying the phosphor content rated paste. After mounting the remote phosphor on top of a blue LED chip, CCT, CRI, and luminance efficiency were measured and values of 5300 K, 62, and 117 lm/W were respectively obtained in the 80 wt% phosphor with 3 coating layers sintered at $800^{\circ}C$.

• Clean Technology
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• v.14 no.1
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• pp.14-20
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• 2008

In this study we have manufactured and characterized the low temperature calcined phosphor paste that can be used as a flat light source for LCD BLU. For the phosphor paste, the low temperature calcined acryl resin was used as the binder. From the result of thermal decomposition measurement, residual carbonaceous materials was found to be less than 0.1 wt% at $400^{\circ}C$. A flat light source device that was made by screen printing using the manufactured paste showed a near 100% luminous efficiency compared to the luminance of the phosphor.

• Electrical & Electronic Materials
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• v.10 no.2
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• pp.150-155
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• 1997

Powder type electroluminescent device(P-ELD) in this study was prepared by printing method. P-ELDs were basically composed of phosphor, insulator and transparent conducting layer. The phosphor powder was prepared by sintering the mixture of ZnS as a host, Cu as an activator, and NaCl as a flux for co-activator and enhancement of growth of the phosphor particles. The phosphor layer was made by printing the paste of the cyanoethylpullan as a binder and the ZnS system phosphor powder. In order to evaluate the luminescence characteristics of ZnS P-ELD, applied voltage - luminance(V-L), frequency-luminance(f-L), and relative luminance spectra(L- .lambda.) characteristics were measured. The experimental results show that luminance increased with increasing the applied voltage and frequency. It can be explained in terms of the potential barrier formed between ZnS and CuS. Two emission peaks in luminance-wavelength spectra measured at applied voltage of 100 $V_{rms}$ were observed at 500nm as a primary peak and 460nm as a secondary peak, respectively.y.

• Proceedings of the Korean Printing Society Conference
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• 2007.11a
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• pp.75-81
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• 2007

As manufacturing the low temperature firing paste applicable flat light source for LCD BLU, this study examined the specific quality. For the phosphor pastes, the low temperature firing acryl resin is used as the binder resin. As the result of thermal decomposition characteristics, residual hydroxylcarbon rested under 0.1wt% on 400$^{\circ}C$. With the manufactured paste in this study, the flat light source device is manufactured through the screen printing and it brought the almost 100% of special quality radiation about the phosphor brightness.

• 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 Institute of Electrical and Electronic Material Engineers
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• v.26 no.4
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• pp.330-334
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• 2013

We developed a package of remote phosphor structure having blue LED chips and phosphors physically separated, and the characteristics were evaluated according to different classifications of phosphor coatings. Remote phosphor was produced by screen printing coating on glass substrate with phosphor content rated paste and heat treatment. After mounting Remote phosphor, which has been classified according to number of coatings, on top of blue LED chips, luminous flux, luminous efficacy, CCT and CRI were measured. The measurement results showed the most suitable characteristics of white LED package as a general light source when the content rate of phosphor in Remote phosphor was 80 wt.% with 3 layers of coatings and thickness over $12{\mu}m$.

• Korean Journal of Optics and Photonics
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• v.26 no.5
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• pp.265-268
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• 2015

An inorganic electroluminescence device based on a green ZnS:(Cu,Al) phosphor was fabricated by a screen printing method. Graphene was added to the phosphor layer to increase the electroluminescence intensity. As the graphene concentration increased, the photoluminescence intensity decreased; on the other hand, the electroluminescence intensity increased, up to 0.6 wt%.

• Transactions on Electrical and Electronic Materials
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• v.12 no.1
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• pp.11-15
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• 2011

In this study, $ZnGa_2O_4$ phosphors in its application to field emission displays and electroluminescence were synthesized through the precipitation method and $Mn^{2+}$ ions. A green luminescence activator, $Cr^{3+}$ ions, and a red luminescence activator were separately doped into $ZnGa_2O_4$, which was then screen printed to an indium tin oxide substrate. The thick films of the $ZnGa_2O_4$ were deposited with the various thicknesses using nano-sized powder. The best luminescence characteristics were shown at a thickness of 60 ${\mu}m$. Additionally, green-emission $ZnGa_2O_4:Mn^{2+}$ and red-emission $ZnGa_2O_4:Cr^{3+}$ phosphor thick films, which have superior characteristics, were manufactured through the screen-printing method. These results indicate that $ZnGa_2O_4$ phosphors prepared through the precipitation method have wide application as phosphor of the full color emission.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1060-1062
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• 2002

Spherical and dense BAM phosphor particles were prepared by spray pyrolysis. The key idea of dense BAM particles is to lead gelation in droplets, which was successfully achieved by using the aluminum polycation as the precursor solution for the spray pyrolysis. The BAM phosphor particles prepared by spraying the aluminum polycation solution have completely spherical shape and dense structure. When directly applied to make phosphor film on the glass by the screen-printing method, the prepared spherical BAM phosphor particles showed better packing density and surface morphology than that of commercial one, which has irregular shape and large particle size. It was also found that the thermal degradation in the photoluminescence intensity for dense and spherical BAM particles was less than that of commercial one.