• 제목/요약/키워드: Brightness Uniformity

검색결과 101건 처리시간 0.029초

Ellipso-Microscopic Observation of Titanium Surface under UV-Light Irradiation

  • Fushimi, K.;Kurauchi, K.;Nakanishi, T.;Hasegawa, Y.;Ueda, M.;Ohtsuka, T.
    • Corrosion Science and Technology
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    • 제15권6호
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    • pp.265-270
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    • 2016
  • The ellipso-microscopic observation of a titanium surface undergoing anodization in $0.05mol\;dm^{-3}$ of $H_2SO_4$ was conducted. During irradiation by ultra-violet (UV) light with a wavelength of 325 nm, the titanium surface allowed for the flow of a photo-induced current and showed up as a bright, patch-like image on an ellipso-microscopic view. The brightness and patch-pattern in the image changed with flowing photo-induced current. The changes in the brightness and the image corresponded to the formation and/or degradation of titanium oxide due to the photo-electrochemical reaction of the oxide. An in situ monitoring using the ellipso-microscope revealed that the film change was dependent on the irradiation light power, by UV-light increases the anodic current and results in the initiation of pitting at lower potentials as compared with the non-irradiated condition.

CRT 디스플레이 시스템의 색재현성 평가 (Evaluation of color reproduction characteristics of CRT display system)

  • 김홍석;박승옥;백정기
    • 한국광학회지
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    • 제10권3호
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    • pp.259-264
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    • 1999
  • CRT 디스플레이 시스템의 입력 신호와 방출되는 빛의 세기 관계를 유도하였다. 빛의 세기는 입력 신호뿐만 아니라 비디오 보드, 전자회로부, 그리고 CRT 특성에도 의존한다. 특히 전자회로부의 증폭률과 옵셋 전압에 따라 휘도 곡선이 크게 달라진다. 본 연구에서는 디스플레이의 contrast 누름 단추와 brightness 누름 단추를 사용하여 전자총의 독립성이 최대로 유지되는 최적상태로 시스템을 설정하였다. 최적상태에서의 디스플레이 시스템의 시간 안정성과 화면 균일도, 그리고 색 선명도를 평가하고, 실제 사용환경을 고려하여 암실과 명실에서의 명암대비를 비교하였다.

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Measurement of Color Uniformity of Liquid Crystal Projection Display

  • Ying, Chen;Haifeng, Li;Mo, Shen;Xu, Liu;Shizhe, Shen
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.483-486
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    • 2004
  • A CCD-based color uniformity measurement system was set up. Through measuring the two-dimensional brightness distributions of three primary colors on the screen, chromaticity coordinate distributions of combination gray can be obtained within a few seconds. This system can be widely used in the production of LCD projection.

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초등학교 교실의 빛 환경 실측에 관한 연구 (A Study on the Experiment of Luminous Environment in Classroom of An Elementary School)

  • 박경은;김준태
    • 교육시설
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    • 제9권5호
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    • pp.13-21
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    • 2002
  • Daylighting in educational environment is very important as it has an effect on students' performance as well as in their visual health. It is regarded as a good energy conservation method in saving energy used for lighting. This study conducted initial daylight measurements to analyze luminous environment in classrooms of Korean elementary school. The results indicated that the typical classroom had a reasonable level of daylight. However, it also found that the classroom had some problems of the uniformity of illuminance and the contrast of brightness of surfaces in the classroom. It is argued that daylighting design for school classroom should consider these aspects to make daylit classrooms ideal so as to provide comfortable visual environment.

Optical Characteristics of a Flexible Back-Light Unit with Plasma Discharge Clusters

  • Goo, Gyo-Uk;Ryu, Si-Hong;Lee, Seung-Eui;Ahn, Sung-Il
    • Transactions on Electrical and Electronic Materials
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    • 제12권5호
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    • pp.189-192
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    • 2011
  • A flexible back-light unit (FBLU) is fabricated by embedding plasma discharge clusters in a flexible polymer matrix. The brightness uniformity of an FBLU was measured for various combinations of optical sheets and compared with the simulated results for various bending angles. A gap between light sources causes distinctive integrated brightness curves which have two inflection points depending on bending angle. The brightness distribution of a simulated BLU was in good agreement with that of an actual plasma BLU except for a dark area that appeared at the center of the simulated BLU. The real and simulated BLUs both clearly showed an angle dependency caused by mirror images located between point light sources. On the basis of these results, it is suggested that these mirror-like images could be a major factor in determining the characteristics of FBLUs.

Comparison on the lighting environment of living room between China and Korea : Comparative study on the lighting environment of houses in Korea and China 1

  • Kim, Hyun-Ji;Jia, Hao;An, Ok-Hee
    • 조명전기설비학회논문지
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    • 제23권11호
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    • pp.1-8
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    • 2009
  • To compare the lighting environment of the living rooms in the apartments in Korea and China, this research conducted a study of the current status, targeting 79 households in Korea and 68 households in China. The results are the following. First, the two nations use mostly fluorescent light as the general lighting for the living room. China, in particular, share of not using the local lighting is very high. Secondly, levels of illumination was measured. The result demonstrates that the brightness of the lighting is higher in Korea compared to China while China demonstrates higher uniformity ratio for the levels of illumination compared to Korea. However, levels of illumination in general are very low in China. Thus, it cannot be concluded that China offers favorable lighting environment. Third, study on the degree of living room lighting's brightness and satisfaction level demonstrates that they are both average in Korea and China. As for the important points for the house lighting, most Koreans cited 'brightness of the lighting' while most Chinese said 'ease of maneuvering'.

직하형 백라이트 설계의 광학시뮬레이션의 응용 (Application of Optical Simulation in Direct-type Backlight Design)

  • 한정민;김병용;강동훈;김영환;김종환;이상극;옥철호;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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    • pp.415-415
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    • 2007
  • In this study. it was investigated about optical simulation in direct-type backlight design. Direct-type backlight has been used high-brightness backlight such as LCD television application. The key parameter in designing direct-type backlight was consists of three geometrical dimension such as the distance of two lamps. the gap of lamp and reflection plate and the number of lamps. It has many variation in optical design and it causes the different properties in backlight system. It shows the best values of above parameters; 26mm of the distance of two lamps. 4.5mm of the gap of lamp and reflection plate and 16 lamps. And we produced the specimen as above condition. and acquired good result in backlight such as the value of the brightness is 6436 nit in center of emission area and less than 5% in brightness uniformity. It shows the effective ways of designing backlight system using optical simulation method.

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Producing Uniform High Illumination Large Area Backlight Systems with Long Life

  • Guzowski, Lawrence T.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.779-782
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    • 2004
  • Establishing and maintaining optimum lamp operating temperature is critically important in backlight systems for large area displays. The information presented in this paper is based upon work completed for a tiled 37.5" AM LCD, plus projections for a 37.5", 42" & 50" monolithic display. Due to the size of the units, a requirement for highly collimated light and a requirement for high brightness, >550 nits at the display surface, significant wattage is required which generates high heat levels in the backlight display assembly and potentially, at the display rear surface. Uniformity of illumination becomes an important element in the system design because of the large area involved.

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A commercial-ready, high resolution AMOLED mobile display with amorphous silicon backplane

  • Church, Corbin;Chaji, Reza;Alexander, Stefan;Nathan, Arokia
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1001-1004
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    • 2008
  • An advanced backplane circuit technology for AMOLED using amorphous silicon TFTs with commercial level reliability, uniformity and lifetime was recently integrated into a prototype device. Differential aging of T98>100 hrs at 200 cd/m2 brightness and >10,000hrs lifetime is demonstrated. A 2.2" QVGA ($240{\times}320$) prototype has been developed and shown having the above-mentioned high performance.

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LED-based illuminated V-core optical engine

  • Chen, Chin-Chung;Mo, Chi-Neng;Wu, Shih-Min
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.560-563
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    • 2006
  • LED is promising for the application of specialty illumination. Thiscolor management system, V-core, with LED light sources and the structure of V-core for LCoS projector has been proposed to improve the primary saturation, uniformity and contrast. We designed the high efficient LED modules for high brightness requirement. The LED module can operate in narrow-direction indicator, $12^{\circ}$.

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