• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.927-930
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• 2004

We report on a new type of a flat and thin display with a secondary emission electron source. In this display device electrons are multiplied between two secondary emission plates under a high frequency electric field. This principle has a few important advantages over a field emission display: the emission comes from flat plates, which reduces the life-time problems of ion bombardment of field emitter tips. Furthermore, the electron emission is space charge limited which gives a uniform electron distribution. The electrons are extracted from the source and accelerated to a phosphor screen to generate light. Gray levels are made by pulse width modulation.

• 한국인쇄학회지
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• 제26권1호
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• pp.97-111
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• 2008

BLU is a important part of the most representative LCD at flat panel display. In order to supplement the optical special quality which LCD cannot light itself, BLU is an essential property to supply with same brightness on the screen. In this study we have manufactured and characterized the low temperature calcined paste that can be used as a flat light source for LCD BLU. For the phosphor paste and intermediate 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 0.2wt% at $400^{\circ}C$.

• 대한의용생체공학회:의공학회지
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• 제8권2호
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• pp.171-176
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• 1987

Wiener filtering method was applied to the dual energy imaging procedure in digital radiography(D.R.). A linear scanning photodiode arrays with 1024 elements(0.6mm H 1.3mm pixel size) were used to obtain chest images in 0.7 sec. For high energy image acquisition, X-ray tube was set at 140KVp, 100mA with a rare-earth phosphor screen. Low energy image was obtained with X-ray tube setting at 70KVp, 150mA. These measured dual energy images are represented in the vector matrix notation as a linear discrete model including the additive random noise. Then, the object images are restored in the minimum mean square error sense using Wiener filtering method in the transformed domain. These restored high and low energy images are used for computation of the basis image decomposition. Then the basis images are linearly combined to produce bone or tissue selective images. Using this process, we could improve the signal to noise ratio characteristics in the material selective images.

• 한국재료학회지
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• 제13권7호
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• pp.424-428
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• 2003

The microstructure and field emission properties of carbon nanotubes(CNT) grown by Ni-catalytic chemical vapor deposition(CVD) were investigated. CVD-grown CNT had a high density of curved shape with randomly oriented. It was found that an increase in electric field caused an increase in field emission current and field emission sites of CNT. The maximum field emission current density was measured to be 3.6 ㎃/$\textrm{cm}^2$ at 2.5 V/$\mu\textrm{m}$, while the brightness of 56 cd/$\textrm{cm}^2$ was observed for the CNT-grown area of 0.8 $\textrm{cm}^2$ from a phosphor screen. Field emission current at constant electric field gradually decreased initially and then stabilized with time.

• 전자공학회논문지A
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• 제31A권5호
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• pp.101-105
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• 1994

The EL lamp have been fabricated by screen printing method. the thickness of BaTiO$_3$ dielectric layer and ZnS:Cu phosphor layer was 20 $\mu$m and 40 $\mu$m, respectively. The threshold voltage of green El lamp was 50 $V_{p-p}$ and the maximum brightness was 13.5 $\mu$ W/cm$^2$ at frequency of 700 Hz and the input voltage of 250 $V_{p-p}$. Also when the Rodamin G6 of 0.02 g was doped, the threshold voltage of white EL lamp was 70 $V_{p-p}$ and the maximum brightness was 34 $\mu$W/cm$^2$.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1087-1090
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• 2008

This paper presents the electro-luminescence (EL) display lamp which is patterned on a curved surface by the pad printing method. The printing methods, including the gravure, screen, flexo, inkjet, and pad printing, have an advantage of one-step direct patterning. However, in general, the printing and semi-conductor process, except pad printing method, cannot be applied for patterning on a curved surface. Thus, in this paper, we used pad printing method for patterning an EL display lamp on a curved surface. The EL display lamp consists of 5 layers: Bottom electrode; Dielectric layer; Phosphor; Transparent electrode; Bus electrode. Finally, we printed EL display lamp on a dish, which has a radius of curvature 80mm. The EL display lamp was driven at AC 200V of 1kHz.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.137-138
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• 2000

We synthesized highly aligned carbon nanotubes by thermal decomposition of acetylene gas using metal catalyst island. The alignment technique in this experiment is a very efficient method because it does not require any treatments before and after catalyst metal deposition. Alignment of nanotubes was dominated by the uniform diameter and the high density of metal catalysts. In the field emission test, the uniform emission spots on phosphor screen were obtained from the nanotubes in spite of non-aligned tube nature.

• 전자공학회논문지B
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• 제31B권6호
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• pp.81-90
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• 1994

Finite element analysis is performed for transient thermal deformation of a shadow mask inside the Braun tube and the landing shift or mislanding of the electronic beam is calclated. The shadow mask has numerous slits through which the electronic beams are guided to land on the designed phosphor. Its thermal deformations therefore cause the mislanding of the electronic beam and result in decolorization of a screen. For realistic finite element analysis, firstly the effective thermal conductivity and the effective elastric modulus are calculated, and the shadow mask is modeled as shell without slits. Next the nonlinear finite element formulation is developed for transient heat transfer on the shadow mask, wherein thermal radiation is a major heat transfer mechanism. Analysis of the resulting thermoelastic deformations is followed, from which the mislanding of the electronic beam is obtained. The present finite element scheme may be efficiently used for thermal deformation design of a shadow mask.

• 한국군사과학기술학회지
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• 제10권3호
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• pp.51-61
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• 2007

This paper concerns about the requirement analysis for night vision imaging system(NVIS), whose purpose is to intensify the available nighttime near infrared(IR) radiation sufficiently to be caught by the human eyes on a miniature green phosphor screen. The requirements for NVIS are NVIS radiance(NR), chromaticity, daylight legibility/readability, etc. The NR is a quantitative measure of night vision goggle (NVG) compatibility of a light source as viewed through goggles. The chromaticity is the quality of a color as determined by its purity and dominant wavelength. The daylight legibility/readability is the degree at which words are readable based on appearance and a measure of an instrument's ability to display incremental changes in its output value. In this paper, the requirements of NR, chromaticity, and daylight legibility/readability for Type I and Class B/C NVIS are analyzed. Also the rationale is shown with respect to those requirements.

• 한국세라믹학회지
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• 제40권12호
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• pp.1170-1176
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• 2003

진화최적방법을 이용하여 alkali earth borosilicate 계열(Eu, Mg, Ca, Sr, Ba)$_{x}$ $B_{y}$S $i_{z}$ $O_{d}$에 E $u^{3+}$ 를 도핑 하여 고효율 적색 형광체를 합성하였다. 본 연구는 삼원색 백색 LED로의 적용을 목적으로 한다. 진화최적방법은 유전알고리즘과 조합화학을 연계하여, LED형광체 개발을 위해 개발하였다. 유전알고리즘을 조합화학에 접목함으로써 시간과 자원의 낭비 없이 매우 효율적인 형광체 탐색을 꾀할 수 있었다. 실질적인 실험에 앞서 다양한 목적함수를 이용하여 시뮬레이션을 실시하여 본 연구의 타당성을 증명하고 실제 합성한 결과 삼원색 백색 LED용 적색형광체(E $u_{0.14}$M $g_{0.18}$C $a_{0.07}$B $a_{0.12}$ $B_{0.17}$S $i_{0.32}$ $O_{{\delta}}$)를 얻었다.얻었다.다.얻었다.얻었다.다.