• 소성∙가공
• /
• 제17권5호
• /
• pp.322-327
• /
• 2008

LGP is a key component of LCD back light unit because it determines brightness and sharpness of the display image. Usually, it has optical patterns fabricated on the bottom surface. These optical patterns convert point or line sources placed in the side of LGP to plane source at the top surface by changing the propagating direction of the incident light. In the present paper the LiGA-reflow method was applied to fabricate the LGP mold. Furthermore, the optical simulation considering the replication ratio of pattern height was applied to the pattern design. The optical simulation through systematic correction scheme was adopted to find the optimum distribution of pattern density. Finally, the stamper fabricated by this method was installed in the mold and LGP was produced by injection molding. As a result of luminance measurement for the final product, the average luminance and luminance uniformity was measured 3,180 nit and 84%, respectively. Consequently, the mold fabrication method using the LiGA-reflow and optical simulation(CAE) can save the expense and time compared with the existing fabrication methods(laser ablation and chemical etching).

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2008년도 춘계학술대회 논문집
• /
• pp.269-272
• /
• 2008

LGP is a key component of LCD back light unit because it determines the brightness and sharpness of display image. Usually, it has optical patterns fabricated on the bottom surface. In the present paper the LiGA-reflow method was applied to fabricate the LGP mold. Furthermore, the optical simulation considering the replication ratio of pattern height was applied to the pattern design. The optical simulation through systematic correction scheme helped find the optimum distribution of pattern density. Finally, the stamper fabricated by this method was installed in the mold and LGP was produced by injection molding. As a result of luminance measurement for the final product, the average luminance and luminance uniformity was measured 3,180 nit and 84%, respectively. Consequently, the mold fabrication method using the LiGA-reflow and optical simulation(CAE) can save the expense and time compared with the existing fabrication methods(laser ablation and chemical etching).

• 한국인터넷방송통신학회논문지
• /
• 제12권6호
• /
• pp.279-283
• /
• 2012

본 논문에서는 모바일용 터치 스크린에서 손가락이 닿는 부분의 좌표를 계산하여 출력하는 저전력 고속 터치 제어 회로를 설계하고 구현하였다. 시스템 클럭은 10MHz이고, 채널 수는 21개, 대기 상태 전류는 $20{\mu}A$ 이고, 다이나믹 레인지는 140pF ~ 400pF 이며, 응답 시간은 0.1ms/frame이다. 저전력을 위한 전력 관리 회로와 보드, 습도, 온도에 따른 자동 임피이던스 보정 기능과 주변 키 및 패턴 간섭 억제 기능 및 직렬 인터페이스 I2C, SPI 기능을 구현하였다. 설계된 제어 회로의 성능은 FPGA와 $0.18{\mu}m$ CMOS 표준 공정을 이용하여 측정하였다. 구현된 제어회로는 모바일 폰이나 스마트 리모트 컨트롤로에 응용할 수 있도록, 다이아몬드 형태를 이용한 2 레이어 ITO용 모듈과 원가절감을 위한 단일 레이어 ITO 모듈에 사용 가능하도록 설계하였다.

• Annals of Clinical Neurophysiology
• /
• 제4권1호
• /
• pp.12-15
• /
• 2002

Background : Changes in firing pattern and in the recruitment order of single motor unit(MU) have been claimed to be characteristic of central motor lesions, and a reduced firing rate was found in upper motor neuron lesions. But these findings have been rarely studied before in Korea, so we studied initial MU recruitment pattern in stroke patients with hemiparesis. Methods : We studied six patients(3 men and 3 women) whose mean age was $60.6{\pm}7.4$ years. A mean $20.6{\pm}16.2$ months had elapsed since the stroke. To compare the initial MU activation patterns in proximal and distal segments of paretic limb with their contalateral unaffected counterparts, we studied the onset and recruitment intervals in biceps brachii(BB) and first dorsal interossei(FDI) muscles in paretic and healthy arms. In a single muscle we examined from 5 to 10 individual MUs. And in a single motor unit, both the onset interval and the recruitment interval was examined. Results : The mean onset interval in paretic limb was significantly(p<0.05) longer than unaffected limb at proximal and distal location: BB $118.5{\pm}17.8$ msec vs $96.1{\pm}8.3$ msec(n=58); FDI $125.8{\pm}16.7$ msec vs $101.5{\pm}17.2$ msec(n=38). The mean recruitment interval in paretic limb was also significantly(p<0.05) longer than unaffected limb: BB $87.7{\pm}14.9$ msec vs $73.4{\pm}11.5$ msec(n=53); FDI $96.3{\pm}16.4$ msec vs $87.7{\pm}14.1$ msec(n=38). Conclusion : The first recruited MU had a lower baseline firing rate and the second recruited motor unit potential appeared earlier in paretic than in healthy muscles. And these findings may explain one of the reasons for paresis in patients with stroke.

• Bulletin of the Korean Chemical Society
• /
• 제22권10호
• /
• pp.1145-1148
• /
• 2001

• 한국전기전자재료학회논문지
• /
• 제36권2호
• /
• pp.158-163
• /
• 2023

Recently, the global demands for high voltage power semiconductors are increasing across various industrial fields. The use of electric cars with high safety and convenience is becoming practical, and IGBT modules of 3.3 kV and 1.2 kA or higher are used for electric locomotives. Delicate design and advanced process technology are required, and research on the optimization of high-voltage IGBT parts is urgently needed in the industry. In this study, we attempted to design a simulation process through TCAD (technology computer-aid design) software to optimize the process conditions of the fielding process among the core unit processes for an especial high yield voltage. As well, the prior circuit technology design and a ring pattern with a large number of ring formation structures outside the wafer similar to the chip structure of other companies were constructed for 3.3 kV NPT-IGBT through a unit process demonstration experiment. The ring pattern was designed with 21 rings and the width of the ring was 6.6 ㎛. By changing the spacing between patterns from 17.4 ㎛ to 35.4 ㎛, it was possible to optimize the spacing from 19.2 ㎛ to 18.4 ㎛.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2000년도 추계학술대회 논문집
• /
• pp.183-189
• /
• 2000

시트 커버 직물은 철도차량 내부 인테리어와 실내를 구성하며, 시각적으로 커버 직물의 디자인 요소 중 패턴과 쾌적한 커버지가 철도차량에 대한 전체적인 이미지를 형성하게 된다. 본 연구는 한국인의 감성에 따른 시트 패던 디자인과 쾌적한 시트 커버 직물의 요건을 제시하고자 한다. 디자인 분석체계는 패턴 디자인의 최소단위를 Pattern Primitive(PP), 최소 반복 단위를 Repealed Pattern Unit(RPU)로 개념화하여 분류하여 파악한다. 또한 쾌적하고 안락한 시트를 위해서 착석 상태에서의 열수분 전달특성과 직물의 발수도, 일광견뢰도, 마찰견뢰도, Q-max, 공기투과도, 마찰대전압 등 물리적 특성을 비교한다.

• 한국광학회:학술대회논문집
• /
• 한국광학회 2008년도 동계학술발표회 논문집
• /
• pp.355-356
• /
• 2008

The light extraction efficiencies of GaN-based light-emitting diodes (LEDs) grown on differently patterned sapphire substrates were investigated by using the ray tracing method. It was found that angle of the pattern surface against the sapphire surface, the number of pattern per unit area were important structural factors for high extraction efficiency.

• 한국감성과학회:학술대회논문집
• /
• 한국감성과학회 1999년도 추계학술대회 논문집
• /
• pp.153-156
• /
• 1999

본 연구는 시트 커버지로 선호하는 직물의 특성을 파악하고자 하였다. 직물디자인의 평가 요소 중 pattern에 초점을 맞추었으며 부수적으로 색상에 대한 선호도 평가를 수행하였다. 직물 pattern 디자인은 PP(Primitive pattern)와 RPU(Repeated pattern unit)의 세부항목에 대한 평가를 통해 전체 직물패턴에 대한 평가가 가능하다. Pattern 특징 평가를 위한 1차 설문에서 소재와 색상의 요인들의 영향을 최소화하기 위해 sample 직물을 gray-scale image로 제시하여 세부항목을 평가하였다. 1차 설문결과로써 pattern 특성을 대표하는 4개의 직물샘플을 선정하였다. 2차 설문에서 4개의 대표 sample을 열차용 시트에 rendering 하여 선호도 평가를 수행하였으며, 색상 선호도 평가는 5가지 색상 군집에 대한 선호를 평가하였다. 선호도 평가 결과 시트 커버지로 선호하는 직물의 특징은 PP의 특징에 상관없이 RPU의 돌출성이 적은 pattern이었다 또한 색상은 초록색과 파랑색을 선호하는 것을 알 수 있었다. 추후 이러한 결과를 통한 시트 커버 직물의 디자인 및 선택이 이루어져야 할 것이다.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2005년도 춘계학술대회 논문집
• /
• pp.51-54
• /
• 2005

Light Guide Plate (LGP) of LCD-BLU(Back Light Unit) is manufactured by forming optical pattern with $5\~100um$ in diameter on the LGP by means of sand blasting or etching method. However, in order to improve the luminance of LCD-LGP, the design of optical pattern has introduced UV inclined-exposure process in this study. This micro-optical pattern, which has asymmetric elliptical column shaped pattern, can change low viewing-angle to high viewing-angle, as well as it contribute to diffusion of light. As a result, this type of micro-optical pattern can introduce the highly luminance. The PR structure obtained in the stage of lithography has asymmetric elliptical column shape and it is processed into a micro-optical pattern. Optical design with this kind of micro-optical pattern, mold fabrication by electroplating and LGP molding with injection molding are under way.