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박동삼;최영현;하민수
- Proceedings of the Korean Society of Precision Engineering Conference
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- 2003.06a
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- pp.1215-1219
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- 2003
Light Guide Panel(LGP) is a key part of backlight unit(BLU) which transforms line-light of lamp to surface-light. Dot pattern is formed on the injected LGP surface by screen printing. This dot pattern is composed of several ten thousands micro dots of diameter 150-180$\mu\textrm{m}$ or so. The dot patterning by screen printing causes low productivity and low performance of TFT-LCD. This research develops the micromachining technology for LGP mould which could form micro dot pattern by injection molding, removing the existing screen printing process.
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Kim, Jung-Hyeon;Hwang, In-Seon
- The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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- v.19 no.1
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- pp.15-21
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- 2005
이제까지 주로 LCD가 대화면화가 진행될 때 CCFL의 기술 개발 동향을 살펴 보았다. CCFL lamp는 LCD module의 BLU에서 광원으로 중요한 자리를 차지해 왔고, 원가 절감 및 성능향상이라는 목표로 지속적으로 기술 개발이 되어 왔다. 하지만 현재 LCD TV가 FPD 시장의 주도적인 역할을 하기 위해서 혁신적인 기술 개발이 요구되어서 EEFL, FFL, LED 광원, CNT 광원 등의 다양한 형태의 광원이 CCFL의 자리를 넘보고 있는 실정이다. 이에 CCFL 메이커들 또한 다른 광원들의 장점을 CCFL 내에서 구현하고, 자신만이 가지고 있는 기술로 주력광원으로서의 자리를 잃지 않기 위해 기술 개발이 더욱 빠르게 이루어져 가고 있다.
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Hwang C. J.;Kim J. S.;Ko Y. B.;Heo Y. M.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 2005.05a
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- pp.51-54
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- 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.
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Cho, S.W.;Kim, J.S.;Hwang, C.J.;Yoon, K.H.;Kang, J.J.
- Transactions of Materials Processing
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- v.20 no.1
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- pp.11-16
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- 2011
Recently, according to the rapid development of display, many display applications, such as, cellular phone, navigation, monitor and LCD TV have been changed from CRT type to LCD type. BLU(Back Light Unit) is one of main parts in LCD unit and generally, it consists of a light source, a reflective sheet, a LGP(Light Guide Plate), a diffuser sheet, and two prism sheets. The most important component of BLU is a light guide plate, which diffuses the input light to the TFT-LCD module uniformly. The LGP is usually made by injection molding process, and it has numerous optical micro patterns on the surface. In the present study the micro-patterned stamper which has cylindrical shape was fabricated by using the UV-LiGA process. And the replication characteristics have been compared among three different kinds of injection molding process; general injection molding, injection/compression molding and RHCM(Rapid Heating and Cooling Molding). Average replication ratios of CIM and ICM were 19.1% and 64.6%, respectively. On the other hand, the average replication ratio of RHCM process showed the higher value of 98.4% among these. It show that maintaining the mold surface above $T_g$ could increase the replication ratio of micro patterns substantially.
https://doi.org/10.5228/KSTP.2011.20.1.11 인용 PDF KSCI

Kim, Dae-Sik
- Proceedings of the Optical Society of Korea Conference
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- 2004.07a
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- pp.232-233
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- 2004
LED 광원의 특성인 높은 색재현성, 친환경성, 저소비전력 등을 디스플레이 광원으로 그 활용도가 높이 평가되고 있다. 최근 비약적인 광효율 증가를 보이고 있는 고출력 LED 광원을 대화면의 LCD TV 용 BLU 와 Projection TV의 조명계에 적용하기 위하여 기술개발에 필요한 주요 요소들을 살펴본다.
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