• 제목/요약/키워드: Young-Hoon Kim

검색결과 9,791건 처리시간 0.05초

High-transmittance Multi-domain Vertical Alignment Liquid Crystal Device with Protrusion Structure

  • Kim, Ki-Han;Jeon, Eun-Young;Park, Byung Wok;Choi, Sun-Wook;Song, Dong Han;Kim, Hoon;Shin, Ki-Chul;Kim, Hee Seop;Yoon, Tae-Hoon
    • Journal of the Optical Society of Korea
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    • 제16권2호
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    • pp.166-169
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    • 2012
  • We propose a high-transmittance multi-domain vertical alignment liquid crystal device with a protrusion structure. Disclination lines, which inevitably appear at the boundaries of domains in a multi-domain structure, can be reduced by adding a protrusion structure on the top substrate. The transmittance was improved by 11% using the proposed structure with no change of either the dark state or the operating voltage.

Simulation and Fabrication of the Cone Sheet for LCD Backlight Application

  • Baik, Sang-Hoon;Hwang, Sung-Ki;Kim, Young-Gyu;Park, Gyeung-Ju;Kwon, Jin-Hyuk;Moon, Won-Taek;Kim, Sung-Hoon;Kim, Byoung-Ku;Kang, Sin-Ho
    • Journal of the Optical Society of Korea
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    • 제13권4호
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    • pp.478-483
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    • 2009
  • An optical sheet with a cone array is designed, simulated, and fabricated in order to substitute the dual crossed prism sheets in the edge-type LCD backlight. The optimum structure of cone textures that is compatible with the dual crossed prism sheets was obtained by simulating the backlight installed with the cone array optical sheet. A SU-8 photoresist films of thickness $30{\sim}50{\mu}m$ were spin-coated on a polyethylene terephtalate film (PET), and the cone texture array was formed by using the diffuse lithography that employed a photomask with circular patterns and an optical diffuser.

Enhancement of the Optical Performance by Optimization of Optical Sheets in Direct-illumination LCD Backlight

  • Park, Gyeung-Ju;Kim, Young-Gyu;Yi, Jong-Hoon;Kwon, Jin-Hyuk;Park, Jae-Hyun;Kim, Sung-Hoon;Kim, Byoung-Ku;Shin, Jong-Keun;Soh, Hoi-Sup
    • Journal of the Optical Society of Korea
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    • 제13권1호
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    • pp.152-157
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    • 2009
  • The structure of the prism sheet and the reflective polarizer sheet in the direct - illumination liquid crystal display (LCD) backlight is optimized and fabricated. The apex angle of the prism sheet was changed from 90 degree to 96.5 and 101.5 degree and the angular spread of the diffuser films attached on the reflective polarizer sheet was changed from 7 to 1.5 degrees. The measured view angle, the normal luminance, and the contrast ratio from the optimized backlight unit showed improved optical performances.

PFN Marx 펄스전원 공급장치 개발 (Development of PFN Marx Pulse Power Supply)

  • 박성수;허훈;김성철;김상희;김승환;박용정;남상훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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    • pp.1562-1563
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    • 2006
  • 고출력 마이크로웨이브의 펄스 전원으로 PFN Marx 펄스 전원공급장치를 설계 및 제작하였다. PFN Marx는 커패시터와 인덕터 그리고 스파크 갭과 전원을 공급하는 전원공급장치와 전류 제한용 저항 또는 인덕터로 구성하여 제작을 하였다. 여기에 사용하는 스파크 갭 스위치는 개스를 채우는 방식으로 개스의 압력을 조정하여 스위치의 스위칭 전압을 조정하여 준다. PFN Marx는 커패시터와 인덕터가 직병렬로 구성이 되며 펄스폭과 PFN의 임피던스를 결정하는 중요한 요소이다. PFN Marx 펄스 전원공급장치를 시뮬레이션 및 제작하여 시험을 할 예정이며 요구되는 사양은 전압 수십 kV, 펄스 폭 수백 ns이다. 본 논문에서는 PFN Marx 펄스전원장치의 설계 및 시험에 대하여 고찰하고자 한다.

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NDLC박막에 DuoPIGatron 이온소스를 사용한 IPS cell의 전기광학특성 (Electro-Optical Performances of In plane Switching(IPS) Cell on the Inorganic Thin Film by DuoPIGatron Ion Source)

  • 김상훈;김종환;강동훈;김영환;황정연;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.453-454
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    • 2006
  • We studied the nematic liquid crystal (NLC) alignment capability by the IB(Ion bean) alignment method on a NDLC(Nitrogen Diamond Like Carbon) as a-C:H thin film. and investigated electro-optical performances of the IBaligned IPS(In plane switching)cell with NDLC surface. A good LC alignment by IB exposure on a NDLC surface was achieved. Monodomain alignment of the IB aligned IPS cell can be observed. The goodelectro-optical (EO) characteristics of the IB aligned IPS cell was observed with oblique IBexposure on the NDLC as a-C:H thin film for 1 min.

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Exchange Bias in Epitaxial Fe/CrSb Bilayer

  • Kim, Jae-Hwi;Choi, Jeong-Yong;Hwang, Young-Hoon;Choi, Jiy-Youn;Cho, Sung-Lae
    • 한국자기학회:학술대회 개요집
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    • 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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    • pp.159.2-159.2
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    • 2007
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