• 한국기계가공학회지
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• 제13권3호
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• pp.111-117
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• 2014

With the development of technology, the display industry has been focusing on the development of new types of displays, such as bendable and wearable displays. However, the PVA/TAC polarizing film used in the manufacturing of a normal display is associated with low luminance and low efficiency. If the existing polarization film is replaced with a wire grid polarizer, it is possible to reduce the thickness significantly. Moreover enhanced brightness can also be expected. This study confirms the optical properties of the WGP through a simulation.

• 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.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.164-169
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• 2002

Recently, LCD(Liquid Crystal Display) is the display product widely used on various fields of industry. This is generally composed of many parts. Among many parts, polarizer film control the intensity of the transmitted light according to the degree of rotation of the polarizer axis. Therefore, this film must be free from defects. But it contains many defects such as the defects caused by dust or different thing, adhesive badness, scratch. Presently, the inspection of these defects is depending on the sight of operator. In this paper, we propose the vision system composed of telecentric lens and optical mirror. This system use the coaxial illumination and the light is specularly reflected on the optical mirror. And we develop the image processing algorithm using the threshold and morphological technique.

• 한국광학회지
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• 제29권6호
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• pp.262-267
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• 2018

본 논문에서는 유기발광다이오드 디스플레이(OLED)의 광 효율을 향상시키기 위해 방사방지필름을 새롭게 디자인하였다. 현재 상용화되고 있는 편광판의 편광도와 투과율을 변화시켜 OLED 반사방지필름에 사용하였을 경우 정면과 측면방향의 반사특성을 계산하였다. 그 결과 편광도가 99.995%나 99.990%인 상용화된 편광판의 편광도를 99.9% 수준으로 떨어뜨릴 경우, 반사방지필름의 평균 시감반사율은 사람의 눈으로 알아차리기 힘든 약 0.1% (증가율 환산 2.5%) 상승한 반면, 투과율은 기존보다 약 1.63~3.34%(증가율 환산 4.2~8.2%) 상승하였다. 이 결과는 기존 OLED에서 저반사율을 유지하면서 광효율을 상승시킬 수 있는 광학설계 조건을 제시하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.822-825
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• 2006

We propose a transflective In-Plane Switching mode in which patterned retarder is placed only on the reflective area of the upper substrate side. By selecting optic axes of Half Wavelength Plate and Liquid Crystal as 24 and 90 degree with respect to polarizer, condition of low reflectance for visible wavelength range at black state is found.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.998-1000
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• 2005

We report the development of the equipment that can measure the transmittance of the polarizer for TFTLCD application versus azimuth angle of the linear polarization at each micro spot in the section, and therefore measure the degree of iodine permeation and alignment quantitatively at each area of the section.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.305-310
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• 2004

We have studied the optimal phase retardation value of a homogeneously aligned liquid crystal (LC) driven by fringe-field when using the LC with positive dielectric anisotropy. In general, the transmittance of a homogeneous aligned LC cell under crossed polarizer is maximum when a twist angle of LC by in-plane rotation is 45$^{\circ}$ with polarizer and the cell retardation becomes λ/2. However, the device using the LC with positive dielectric anisotropy does not follow this since the degree of rotation of the LC is dependent on electrode position and in addition the LCs tilt up along the fringe-field. At the center of common and pixel electrode, the LC is most twisted around a middle position of a cell whereas at the edge position of pixel electrode, the LC is most twisted near bottom surface of a cell. Consequently, the optimal phase retardation of the device becomes much larger than λ/2 and the transmittance can be described using the combination of the in-plane switching and twisted nematic mode.

• 한국광학회지
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• 제8권3호
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• pp.223-229
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• 1997

베레만의 4 * 4행렬방정식을 써서 액정판의 편광투과특성을 분석하는 프로그램을 개발하고, 이를 써서 액정셀과 편광판의 편광투과특성을 살펴보았다. 개발된 프로그램을 써서 정상백색 모우드의 꼬인 네마틱(TNLTwisted Nematic) 액정셀에서 시야각에 따른 명암대비의 변화를 보여주는 등고선을 그려내어 그 특성을 예측할 수 있었다. 또한 편광판의 투과특성은 입사각이 커짐에 따라 투과된 빛의 편광타원의 주축이 투과축 방향에서 벗어나며 타원도가 커지는 것이 밝혀졌는데, 이 결과는 액정표시소자의 명암대비가 액정판만이 아니라 편광판의 특성에 의해서도 제한될 수 있음을 시사한다.

• 한국광학회지
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• 제20권1호
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• pp.48-52
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• 2009

파장 514.5 nm에서 8.4 um 두께의 ECB(Electically Controlled Birefringenence) 액정 셀과 1/4 파장판을 이용하여 간단하게 360도 이상으로 선형편광의 방향을 광손실없이 자유롭게 바꿀 수 있는 선형편광 회전기를 제안하고 이를 구현하였다. 이 선형편광 회전기의 편광도는 0.964이며, 1주일간의 시간적 변화도 ${\pm}1$도 정도로 시간적 안정성이 매우 뛰어남을 확인하였다. 이 선형편광기의 전압 대회전각의 비선형성 문제는 사용할 전압범위를 바꾸거나 이 선형편광 회전기의 회전각에 대한 피팅곡선을 사용하면 쉽게 해결할 수 있다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.991-994
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• 2005

We have successfully commercialized a novel optical compensation film, OCB-WV film, for OCB-LCD-TVs which has fast response time and wide viewing angle. The OCB-WV film consists of a 45degree-aligned discotic layer and a high Rth biaxial TAC film, which is suited for a roll-to-roll polarizer manufacturing process. This OCB-WV has brought out the excellent features that OCB intrinsically has, making nextgeneration fast-response LCD-TVs possible and free from image blurring in conjunction with an impulsive driving scheme.