• Current Optics and Photonics
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• 제1권2호
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• pp.101-106
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• 2017

Optical structures of a tapered ultra-thin light guide film (LGF) were optimized by optical simulation for increasing coupling efficiency between light sources and the LGF. A serration pattern on the entrance side surface could provide a comparable coupling efficiency to that of the conventional LGF where a linear, asymmetric prism array was formed on the taper surface. Several micro-patterns were applied to the top and/or bottom surface of the LGF for achieving better luminance property, and it was found that an optimized micro-pyramid pattern exhibited the highest average luminance together with satisfactory luminance uniformity.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.514-517
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• 2005

Microstereolithography(MSL) has evolved from the stereolithography technique, and is also based on a light-induced layer-stacking fabrication. Although integral MSL allows the manufacture of a complete layer by one irradiation only, there is a problem related with shape precision due to the light-intensity distribution of focused image. In this study, we developed the integral MSL apparatus using Digital Micromirror Device ($DMD^{TM})$, Texas Instruments) as dynamic pattern generator. It is composed of Xenon-Mecury lamp, optical devices, pattern generator, precision stage, controllers and the control program. Also, we have studied curing depth and width of photocurable resin according to the change of exposure energy.

• 한국전기전자재료학회논문지
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• 제28권3호
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• pp.175-179
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• 2015

In this study, we propose Ti hole pattern structure on the transparent conductive oxide (TCO) less dye-sensitized solar cells (DSSCs) using the lift-off process to improve the low light transmittance and low efficiency caused by opaque Ti electrode. The formation of Ti hole patterns make it possible to move the dye adsorption and electrolyte. The DSSCs with Ti hole patterns showed a higher photoelectric conversion efficiency (PCE) than those with general structure by 11.1%. As a result, The Ti hole pattern structure can be improved to increase the light absorption of the dyes and PCE of the TCO-less DSSCs is also increased.

• 한국광학회지
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• 제19권1호
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• pp.43-47
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• 2008

현재 TFT-LCD(Thin Film Transistor Liquid Crystal Display)에 사용되는 BLU(Back Light Unit) 패턴 크기는 수 십 ${\mu}m$인데 반해, 최근에는 BLU 패턴의 크기를 수 ${\mu}m$ 또는 그 이하로 조절함으로써 출력광의 휘도를 증가시키고 균일도를 향상시키고자 하는 연구가 진행되고 있다. 본 연구에서는 패턴의 크기, 분포 및 점유 면적이 출력광의 분포에 미치는 영향을 조사하였다.

• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 하계학술발표회 논문집
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• pp.285-286
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• 2007

Current distributions according to electrode patterns in vertical structured InGaN/GaN LED (light emitting diode) were investigated quantitatively by utilizing three dimensional electrical circuit modeling method. The uniformity of the injected current density in the active layer was compared among different electrode patterns. It was found that the current uniformity was greatly dependent on the electrode pattern in vertical InGaN/GaN LEDs.

• Journal of Plant Biology
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• 제2권1호
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• pp.35-42
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• 1959

1. 발아시부터 단일, 암기저온 조건하에서는 괴근은 전연 형성되지 않고, 장일조건에서만 괴근이 형성됨. 따라서 장일조건이 고구마괴근 형성에 대한 유도조건 내지 촉진조건임을 알 수 있다. 2. 본실험은 시종 약전광(300W 전구 사용)으로 재배하였기 때문에 동화작용이나 생장이 특히 미약한 상태에서도 괴근이 유도되었다. 따라서 괴근형성에는 동화물질이나 생장보다도 장일조건이 직접적결요인을 이루는 1종자극을 성립하는 것으로 보인다. 3. 장기조건과 단일조건하의 근계가 서로 특이한 상태를 나타냈고 그것은 단일과 장일조건이 이룬 자극과 관계하는 것으로 보인다. 4. 고구마괴근이 장일조건에 유되되는 사실의 생태학적 의의를 고찰함.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.134-134
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• 2004

LCD-BLU의 고효율 광특성을 유도하기 위한 도광판의 초미세패턴 형상가공기술, 미세사출성형기술과 미세형상패턴 광학해석기술 및 전광특성 측정 및 보완기술이 요구된다. 이러한 기술들을 바탕으로 LCD-BLU의 고단가의 주요요인인 기능성 광학 sheet(prism sheet 등)를 연차적으로 제거 및 도광판에 기능을 결합하는 기술개발이 본 연구의 목적이다.(중략)

• 한국도로학회논문집
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• 제15권5호
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• pp.111-122
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• 2013

PURPOSES : The purpose of this system (Rear Lighting System) is to provide illumination for the driver to operate the commercial vehicle safely after dark in highway, to increase the conspicuity of the vehicle, and especially be suggesting the finest observable improvement method, depending on color and pattern of rear lighting system of truck for midnight highway traffic. METHODS : Rear lightning system as an improving way for forward commercial vehicles lighting the securing sight from human factors and the surrounding environment in midnight driving. For this one, basic materials were collected from the data analysis about many types of problems, and filed investigation for establishing Driving Simulator. also taking statistic test to human volunteers after finding recognizable distance of them. RESULTS : As a result, color with the highest visuality is amber followed by green-red-blue as in order for all road types. Especially almost no difference is found between red and green, also when the light is turn off, recognizable distances is wide difference compared to turn on the light. One more thing about study per pattern, upper and entire lighting have similar recognizable distances, but under lighting shows short distance with difficulty securing sight from medians. And straight section shows similar recognizable distances. By finding visuality improvement method depending on color and pattern of supplement taillight, it is expected to suggest quantitative judgement standard for introducing regulation and improvement of supplement taillight. CONCLUSIONS : Night time vehicle conspicuity to the rear is provided by rear position lamps. this study is showed that the color of light ramp is not important to be safe driving, most important is to turn on the light, recognizable distances is big different compared to turn off the rear light, so when the drivng dark in highway, have to turn on the light for reducing risk.

• 한국방사선학회논문지
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• 제11권5호
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• pp.401-406
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• 2017

유방암 발생률이 해마다 증가하여 그에 따라 유방 종양을 진단하는 검사인 조직검사의 횟수도 같이 증가하고 있다. 조직검사는 침습적 검사로써 환자들의 불안감과 감염, 출혈 등의 부작용이 발생하고 있다. 본 연구에서는 유방 병변 환자를 대상으로 회색조 초음파와 탄성초음파검사 모두 실시한 69명을 대상으로 회색조 초음파는 BI-RADS Category에 따라 분류하고, 탄성초음파검사는 횡파의 전파 속도를 환산하여 나타낸 kPa값을 Color overlay pattern으로 분류하였다. 민감도와 특이도의 합이 가장 높은 최적의 Cut-off value는 54.70 kPa로 나타났다. Color overlay pattern에서 Dark Blue 42명, Light blue ~ Red 27명으로 분류된 결과와 BI-RADS Category 분류 결과인 양성 40명, 악성 29명으로 분류된 결과가 유사하다. 따라서 Color overlay pattern에서 Dark Blue에 분류될 경우에는 양성, Light blue ~ Red에 분류될 경우에는 악성으로 의심할 수 있을 것으로 판단된다. 결론적으로 유방 탄성초음파는 무분별한 유방 조직검사의 횟수를 줄이고 양성종양과 악성종양을 구분하는데 획기적인 역할을 할 것으로 사료된다.

• 한국정밀공학회지
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• 제23권9호
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• pp.174-178
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• 2006

Pyramid shape of micro pattern is applied to the light guide panel (LGP) to enhance the uniformity of the brightness of the LCD. The micro pyramids are molded in intaglio on the surface of the LGP. The size of each pyramid is 5$\mu$m $\times$ 5$\mu$m on bottom and the height is about 3.5$\mu$m. The pyramids are distributed on the LGP surface randomly to be sparser where the light comes in and denser at the opposite side as a result of a simulation using lightools$^{TM}$ Based on this design, a silicon pattern master and a nickel stamper are fabricated by MEMS process and electro plating process. Intaglio micro pyramids are fabricated on the 6' of silicon wafer from the anisotropic etching using KOH and the process time, temperature of the KOH solution, etc are optimized to obtain precise shape of the pattern. A Wi stamper is fabricated from this pattern master by electro plating process and the embossed pyramid patterns turns out to be well defined on the stamper. Adopting this stamper to the mold base with two cavities, 1.8' and 3.6' LGPs are injection molded.