• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.591-595
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• 1990

This paper describes a method of aisle following of a mobile robot using machine vision. As a navigation guide, Black strip painted on the lower part of wall of aisle is used. The offset of the vehicle position from the center of aisle and the heading angle are determined from the binary image of guide strip captured by a CCD camera. To remove the effect of noise. i.e. break of guide strip for the door or reflection of light, pixel sampling method together with consistency check of the incline for the sampled pixels is used.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.221-224
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• 2003

Recently, the market share of the thin-film-transistor liquid-crystalline-display (TFT-LCD) is growing rapidly in display device market. The backlight unit is used as a light source of TFT-LCD module. A light-guide is one of several important components of backlight unit. The manufacturing technology and optical system design of the light guide is very sensitive to quality and cost of the TFT-LCD module. In the present study a new manufacturing method which is called as direct surface forming(DSF) has been tested under various conditions. The result of this test, V-groove pattern shows different shapes depends on the temperature of mold surface, contact time of mold and depth of V-groove.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.10a
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• pp.527-528
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• 2006

• 전기의세계
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• v.31 no.5
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• pp.383-390
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• 1982

The high power glass laser system was designed and constracted which consisted of a TEM$\_$00/ mode Q-switching oscillator, a pulse shaping, system, two-stage pre-amplifiers, five-stage main amplifiers, a Faraday rotator, and a uni-guide slit. The laser output of 3OGW with the pulsewidth of 2 nsec was obtained by performing the amplifiing experiment in this system. When the laser light with the pulsewidth of 10 nsec was amplified, the large factor of amplification was obtained in the beginning of pulse, but the factor of amplification decreased gradually in the later part of pulse. Therefore, the laser light which has short pulsewidth of-2nsec must be amplified in order to obtain the larger factor of amplification. When the laser beam from the high power glass laser system was irradiated to plasma, the reflected laser light from plasma which occured inevitably could be attenuated to the order of 10$\^$-4/ by using the Faraday rotator and the uni-guide slit.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.217-224
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• 2005

A light-guide plate of an LCD backlight coupled with a microfresnel lens array (MFLA) is designed and analyzed. Computer simulated results of optical characteristics of our MFLA-type light-guided plate compared with the conventional prism-type one are presented. We show that the MFLA-type light-guide plate can replace well the conventional prism-type plate.

• Biomedical Science Letters
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• v.25 no.4
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• pp.372-380
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• 2019

Mice with specific modified genes are useful means of studying development and disease. The CRISPR/Cas9 system is a very powerful and effective tool for generating genetically modified mice in a simple and fast manner. To generate human IgG light kappa constant knock-in mice, we tested by microinjection of a mixture of Cas9 protein, single-guide RNA and target homologous recombinant donor DNA into zygotes. We found that the injection of 10 ng/μL of Cas9 protein and crRNA/tracrRNA, rather than single guide RNA, induced the production of knock-in mice more effectively. Thus, our study provides valuable information that will help to improve the production of knock-in mice and contribute the successful generation of humanized Ab-producing mice in Korea.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.578-581
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• 1999

Dot pattern print methods composed of a diffusion film and two prism sheets, have been generally used for backlighting systems of LCDs. However, this methods require complex structures and show high power consumption and optical loss. To improve these disadvantages of conventional backlight units, light guides using highly scattering optical transmissions (HSOT) polymer as scatters, have been introduced. In this study we analyzed multiple scattering effect in light guide by means of Monte carlo simulation based on Mie scattering theory and ray tracing method. As a result it was revealed that scattering intensity depends on the size of scatters. On the other hands, it was shown that scattering efficiency depends on the wavelength of fluorescent lamp as well as the size of scatters.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.1871-1878
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• 2014

PMMA (Polymethyle-methacrylate) optical components have recently been increasingly used as one of the important part of the high precision equipments. This research presents comparatively the surface preparation of light incident plane, LIP (Light Incident Plane) of LGP (Light Guide Panel) by end milling, high speed shaping, and vibration assisted high speed shaping. From several experiments, the results show that the surface quality was improved in high speed shaping and the vibration assisted HSS show not only decreasing waviness and breakage also raising the straightness property. For applying high speed shaping and vibration assisted HSS, an additional tool post was developed and experimentally used.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.216-219
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• 2005

In recent, LCD becomes one of the main display devices and expected to have quite good market share during the next couple of years. The demand for low cost and high performance, however, is becoming severe as the competition among other display devices like PDP, OLED increases. To satisfy this demand from market, we need to optimize the parts or modules of the LCD, reduce the number of the assemble and enhance the process for the high brightness and uniformity of the LCD. The LCD consists mainly of LCD panel and Backlight unit(BLU). BLU, which takes big portion of the cost for LCD, consists of light source, light guide panel and many kinds of functional film. Recently light guide panel or film for BLU has micro patterns on its surface and consequently to reduce the number of parts and enhace the brightness and its uniformity. In this study, some methodologies for the fabrication of the master/stamper and molding the light quide panel are introduced for 50um pitch of prizm patterned substrate. Mechanical machining process is adapted and optimized to fabricate micro patterned stamper using the micro cutting tool. Injection molding technology is also developed to obtain uniformly replicated micro patterned products.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.432-432
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• 2007

We studied optical simulation method for ultra slim backlight system. We designed 0.7mm thickness light guide plate and combined 48 white color LEDs for 12 inch wide size TFT-LCD. We designed flat shape PMMA light guide plate with both side patterned. It have vertical prism shape on upper side and ellipse dot pattern on the other side. We targeted 4500 nit brightness and uniform emission characteristic without hot spot or dark area. At first, we designed uniform emission area with more high brightness in center area and then, debugged light entering hot spot zone and direction of outgoing light flux. Although it was designing step, we obtained good result with reverse prism optical sheet and it had good repeatability because it was based on the stamper method in injection process without laser engraving or micro groove engraving method.