• 제목/요약/키워드: Brightness temperature

검색결과 450건 처리시간 0.028초

LCD TV 백라이트 구동특성 개선을 위한 면광원 인버터 개발 (Development of Flat Fluorescent Lamp (FFL) Inverter for Improvement of LCD TV Backlight Driving Characteristics)

  • 허정욱;임성규
    • 전자공학회논문지 IE
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    • 제44권2호
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    • pp.47-53
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    • 2007
  • 본 논문에서는 Level Control Block (LCB)를 이용한 면광원 인버터를 개발하여 면광원을 이용한 LCD TV 백라이트의 구동특성이 향상되었음을 확인하였다. 또한 LCB를 사용하여 면광원의 시동 시간, 휘도 안정화 시간, 전류의 크기를 조절할 수 있고 개선됨을 확인할 수 있었으며, LCB를 이용하여 면광원램프를 사용한 LCD TV용 백라이트를 넓은 온도범위에서 안정되게 동작시킬 수 있었다.

3투사렌즈방식 LCD 프로젝션 TV의 엔진 냉각에 관한 연구 (A study on the cooling method for LCD projection TV with 3 projection lens)

  • 김철환;조여욱
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1253-1257
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    • 2004
  • We have developed new rear LCD Projection TV engine with 3 projection lens. It has high brightness and contrast ratio, however poor cooling conditions. If optical components close to light source, optical components are damaged on high temperature, especially the blue among RGB colors is weakest by heat In this study, a new enhanced cooling method of LCD projection TV with 3 lens is shown: the best suited design of duct and relations between LCD panel and polarizer lifetime with changed area of duct.

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색지 폐지의 광학적 특성에 미치는 환원 표백의 영향 (Effect of Reductive Bleaching on Optical Properties of Color Ledger)

  • 안병준;백기현
    • 펄프종이기술
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    • 제33권2호
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    • pp.68-73
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    • 2001
  • This experiment was executed to clarify the optimum condition of reductive bleaching for 100% color papers. The reductive bleaching of the color paper was desirable to be done under such conditions as high temperature over $60^{\circ}C$ and high consistency within possibly short time. The FAS bleaching like the sodium hydrosulfite required oxygen-free condition. Especially, as the mixture between pulps and chemicals was favored in case of the high consistency, it was actively recommended. Therefore, it is desirable to control the dosage with the type of the dyes, the nature, the dye content, the paper compositions, and the targeting initial and final brightness.

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항공기 디스플레이용 LED Backlight의 광대역 Dimming Controller 구현 (Implementation of Wide-Range Dimming Controller of LED Backlight for Avionics Displays)

  • 임수현;임정규;신휘범;정세교;신민재;손승걸
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2007년도 추계학술대회 논문집
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    • pp.53-55
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    • 2007
  • This paper describes an implementation of a wide-range dimming controller of a LED backlight for Avionics applications such as the control data unit(CDU) and multi-function display(MFD). A feedback controller using a light sensor is proposed to control the brightness in the low dimming range. The proposed controller provides an improved control performance in the wide dimming range of 1:3000 even under the temperature variations. The experimental results are provided to show the effectiveness of the proposed control system.

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Video Phone Tube用 형광박의 제조에 관한 연구 (A Study on Manufacture of Phosphor Screen for Video Phone Tube)

  • 우진호
    • 한국인쇄학회지
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    • 제22권2호
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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.

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가속시험을 통한 Electroluminescent film의 활성화 에너지 추정 (Estimation of Activation Energy of Electroluminescent film by Accelerated Life Test)

  • 김수경;형재필;오길구;임홍우;김명수;오근태
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제15권1호
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    • pp.52-59
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    • 2015
  • In this Study, we tested electroluminescent film to accelerate life by temperature, humidity, voltage, and frequency. We analyzed brightness data to estimate activation energy and verify it's suitability. All of the tests performed in operating condition. Because electroluminescent film is mostly degraded by fluorescent in operating condition. Two different sample groups were tested and compared to find common parameter.

$T_{b}$-$N_{HI}$ CORRELATION IN THE GALACTIC PLANE

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • 제17권1호
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    • pp.33-38
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    • 2000
  • Synchrotron emission at 408 MHz and HI column density have been used to find an evidence for the relationship between the Galactic magnetic field and the gas density. The observational data of the brightness temperature and HI column density, $T_b(408)\;and \;N_{HI}$, near the galactic plane between galactic longitudes $l=62^{circ}\;and\;l=250^{\circ}$ show a clear linear correlation of $T_b(408)=A(l,b)+B\;N_{HI}$, where A(l, b)is a background and forground radiation at the galactic coordinate. We found $(1.4{pm}0.3)10^{-21}$ for the slope B, which describes the strength of the syncrotron radiation from the HI cloud, and agrees with the value for the MIlky Way obtained by Beuermann et al. (1985). We conclude therefore that a well defined nonthermal corelates with the HI column density originating from this HI cloud.

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Rainfall Intensity Estimation with Cloud Type using Satellite Data

  • Jee, Joon-Bum;Lee, Kyu-Tae
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.660-663
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    • 2006
  • Rainfall estimation is important to weather forecast, flood control, hydrological plan. The empirical and statistical methods by measured data(surface rain gauge, rainfall radar, Satellite) is commonly used for rainfall estimation. In this study, the rainfall intensity for East Asia region was estimated using the empirical relationship between SSM/I data of DMSP satellite and brightness temperature of GEOS-9(10.7${\mu}m$) with cloud types(ISCCP and MSG classification). And the empirical formula for rainfall estimation was produced by PMM (Probability Matching Method).

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유리기판 위에 성장된 카본나노튜브를 이용한 고휘도 램프 특성 (Development of flat type back-lamp using carbon nano tubes grown on glass substrate)

  • 이양두;이덕중;박정훈;유재은;이윤희;장진;주병권
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.89-92
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    • 2002
  • Carbon nano tubes(CNTs) have been reported as field emission source because has a sharp tip, a high aspect tip, high chemical stability, high mechanical strength and low work function properties. In this study, we fabricated successfully the back-lamp of the I-inch flat type using CNTs, which was grown directly on cathode substrate of sodalime glass at low temperature. The brightness of CNT back-lamp is measured to $14 Kcd/m^{2}$ at $2000V_{dc}$ in spacing of $500{\mu}m$. And, the emission properties of packaged CNT back-lamp was analyzed as function of applying voltage and times.

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zigbee 통신을 이용한 LED 조명 제어 시스템 구현 (Implement of The LED lighting control system using Zigbee Communication)

  • 조성재;이성민;문철홍
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.323-324
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    • 2008
  • This study implemented the LED lighting control system using Zigbee Communication. We designed a desk lamp using LEDs. The PWM signals control LEDs using LED drivers. A desk lamp received PWM signals using Zigbee protocol to control LED Color, Color temperature and brightness. Zigbee protocol that have such several advantages to existent Home network system can upgrade more interface dimension.

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