• Korea Multimedia Society
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• v.8 no.1
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• pp.27-34
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• 2004

최근 주요 이동통신 사업자, 단말기/칩 제조업체, 콘텐츠 제공업자들 사이에는 모바일 3D분야가 가장 커다란 이슈가 되고 있다. 지금까지 모바일 시장은 많은 발전을 하여 왔다. 초기의 핸드폰을 보면 우리는 농담으로 무전기라는 표현을 하곤 했다. 모바일 단말기는 규모가 작아지기 시작했고, 벨소리도 처음엔 단음에서 지금은 64폴리를 지원하고 있으며, LCD화면 또한 지원하는 화소가 상상을 넘어서고 있다. 하지만 이렇게 급속하게 발전하던 모바일 분야도 지금 한계에 부딪혀 있다. 사용자의 요구를 좀더 충족시키고, 이동통신 사업자들과 단말기 및 칩셋 제조회사들은 자사의 경쟁력을 강화해 주기 위한 새로운 대안으로 모바일 3D 분야가 떠오르고 있다[2].(중략)

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1345-1349
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• 2009

We developed a glasses-free 3D stereoscopic display using an LCD display panel, a view control film and a grating film for stereoscopic viewing. The observer can watch overlapped stereoscopic images for left and right eyes without special glasses such as polarized glasses.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5C
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• pp.716-725
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• 2004

In this paper, a new multiview stereoscopic 3D display system using a VHLS(volume holographic lenticular sheet) is suggested. The VHLS, which acts just like an optical direction modulator, can be implemented by recording the diffraction gratings corresponding each directional vector of the multiview stereoscopic images in the holographic recording material by using the angularly multiplexed recording property of the conventional volume hologram. Then, this fabricated VHLS is attached to the panel of a LCD spatial light modulator and used to diffract each of the multiview image loaded in a SLM to the corresponding spatial direction for making a 3D stereo view-zone. Accordingly, in this paper, the operational principle and characteristics of the VHLS are analyzed and an optimized 4-view VHLS is fabricated by using a commercial photopolymer. Then, a new VHLS-based 4-view stereoscopic 3D display system is implemented. Through some experimental results using a 4-view image synthesized with adaptive disparity estimation algorithm, it is suggested that implementation of a new VHLS-based multiview stereoscopic 3D display system can be possible.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.145-148
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• 2012

In applying LCD to TV application, one of the most significant factors to be improved is image sticking on the moving picture. LCD is different from CRT in the sense that it's continuous passive device, which holds images in entire frame period, while impulse type device generate image in very short time. To reduce image sticking problem related to hold typedisplay mode, we made an experiment to drive TN-LCD like CRT. We made articulate images by turn on-off backlight, and we realized the ratio of Back Light on-off time by counting between on time and off time for video signal input during 1 frame (16.7ms). Conventional CCFL (cold cathode fluorescent lamp) cannot follow fast on-off speed, so we evaluated new fluorescent substances of light source to improve residual light characteristic of CCFL. We realized articulate image generation similar to CRT by CCFL blinking drive and TN-LCD overdriving. As a result, reduced image sticking phenomenon was validated by naked eye and response time measurement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.665-668
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• 2012

This paper describes research results that 2-D contents, which display in smart phone or tablet PC to be able to see the 3-D stereoscopic by use projection technique. For this research, we have construct four brown-glass into pyramid shape, project each of the four LCD monitors that output from the PC screen into of the four inverted pyramid-shaped mirror and display the 3-D image to the center of the mirror system. For the test, We use tablet PC and server PC(desktop PC) connected by wireless network, tablet PC select contents which is displayed in the server PC, and displayed selected contents into the 3-D image to the center of the mirror system. Through the test, we have showed that it is possible to display 3-D stereoscopic to the 2-D contents by use projection technique. Although, display image is depending on the observer's viewing angle.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.4C
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• pp.524-532
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• 2004

In this paper, an incoherent holographic 3D imaging and display system based on the modified triangular and Mach-Zehnder interferometers is optically implemented and some experiments are carried out. Incoherent hologram of a 3D object is generated by using the hologram input system of modified triangular interferometer. Then this complex hologram is reconstructed by using the hologram output system of modified Mach-Zehnder interferometer in which two LCD spatial light modulators and a waveplate are inserted. From the experiment with two point sources having a depth difference of 100 mm each other, it is revealed that each point source can be independently reconstructed at its own focal position from the complex hologram, while both of the bias and conjugate image are simultaneously eliminated at the same time. And in the experiment with the real 3D object of two dices having a depth difference of 30 mm each other, it is also conformed that the bias and conjugate image can be effectively eliminated from the hologram pattern and each 3D dice can be also successfully reconstructed at its own focal position from the complex hologram. These experiment results finally suggest a possibility of implementing a new incoherent holographic 3D imaging and display system using the modified triangular and Mach-Zehender interferometers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05a
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• pp.206-209
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• 2004

We investigated response characteristics of liquid crystal display(LCD) with different operating mode of nematic liquid crystals (NLCs) such as $45^{\circ}$twist nematic (TN), $67.3^{\circ}$TN and ECB(electrical controlled birefringence) on a rubbed polyimide (PI) surface. The three kinds of LCD operating mode obtain stable EO performance. Low transmittances of the $45^{\circ}$TN and $67.3^{\circ}$TN cell on the rubbed PI surface were achieved by using low cell gap d. The fast response time of ECB cell among the three kinds of LCD operating mode was measured.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.149-150
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• 2007

In this paper, we propose a novel defects inspection algorithm for TFT-LCD panels. We first compensate the distorted image caused by the camera distortion and the uneven illumination environment using the least squares method and the bezier surface. We find a starting point of each pattern. The reference frame, made by subtract method using several clean patterns, is compared to each pattern to find defects. The simulation example shows that our algorithm not only inspects the defects well, but also is robust to the 1-pixel error.

• The Journal of Advanced Prosthodontics
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• v.14 no.6
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• pp.379-387
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• 2022

PURPOSE. The aim of this study is to compare the casts obtained by using conventional techniques and liquid crystal display (LCD) three-dimensional (3D) print techniques in the All-on-4 treatment concept of the edentulous mandibular jaw. MATERIALS AND METHODS. In this study, a completely edentulous mandibular acrylic cast (typodont) with bone-level implants placed with the Allon-4 technique served as a reference cast. In this typodont, impressions were taken with the conventional technique and dental stone casts were obtained. In addition, after scanning the acrylic cast in a dental laboratory scanner and obtaining the Standard Tessellation Language (STL) data, 3D printed casts were manufactured with a 3D printing device based on the design. The stone and 3D printed casts were scanned in the laboratory scanner and STL data were obtained, and then the interimplant distances were measured using Geomagic Control X v2020 (3D Systems, Rock Hill, SC, USA) analysis software (n = 60). The obtained data were statistically evaluated with one-way analysis of variance (ANOVA) and Tukey's pairwise comparison tests. RESULTS. As a result of the one-way ANOVA test, it was determined that the stone casts, 3D printed casts, and reference cast values in all distance intervals conformed to the normal distribution and these values had a significant difference among them in all distance intervals. In Tukey pairwise comparison test, significant differences were found between casts at all distance intervals. In all analyses, the level of significance was determined as .05. CONCLUSION. 3D printed casts obtained with a 3D LCD printing device can be an alternative to stone casts when implants are placed in edentulous jaws. [J Adv Prosthodont 2022;14:379-87]

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.4
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• pp.362-368
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• 2001

The goal of this paper is development ofa DSP based three phase power quality analyzer. Power analysis algorithm is a correlation function and it is accomplished using stand alone type TMS320C31 DSP(digital signal processor)board. Results of power analysis are displayed by LCD and D/A converter on the proposed system. Finally, this paper also goes on to discuss the performance of an instrument prototype, compared with one of those foreign models, both in terms of accuracy and speed of measurement.