• Journal of the Optical Society of Korea
• /
• 제18권6호
• /
• pp.706-713
• /
• 2014

An enhanced 360-degree integral-floating three-dimensional display system using a hexagonal lens array and a hidden point removal operator is proposed. Only the visible points of the chosen three-dimensional point cloud model are detected by the hidden point removal operator for each rotating step of the anamorphic optics system, and elemental image arrays are generated for the detected visible points from the corresponding viewpoint. Each elemental image of the elemental image array is generated by a hexagonal grid, due to being captured through a hexagonal lens array. The hidden point removal operator eliminates the overlap problem of points in front and behind, and the hexagonal lens array captures the elemental image arrays with more accurate approximation, so in the end the quality of the displayed image is improved. In an experiment, an anamorphic-optics-system-based 360-degree integral-floating display with improved image quality is demonstrated.

• 한국반도체및디스플레이장비학회:학술대회논문집
• /
• 한국반도체및디스플레이장비학회 2006년도 춘계학술대회
• /
• pp.105-108
• /
• 2006

We investigated the fluidic gas-driven carbon-nanotube motor based on multi-wall carbon nanotubes and fluidic gas flow. Since the origination of the torque was the friction between the carbon nanotube surface and the fluidic gases, the density and the flow rate of the working gas or liquid were very important for the carbon nanotube motor. Molecular simulation results showed that multi-wall carbon nanotubes with very low rotating energy barriers could be effectively used for fluidic gas-driven carbon-nanotube motors.

• 한국해양공학회:학술대회논문집
• /
• 한국해양공학회 2004년도 학술대회지
• /
• pp.395-400
• /
• 2004

For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established. Bearing diagnosis system is composed of four parts as follows : sensing part for ultrasonic sensor and preamplifier, signal processing part for measuring frequency spectrum, energy and amplitude, interface part for connecting ultrasonic signal to PC using A/D converter, graphic display and software part for display of bearing condition and for managing of diagnosis program.

• 반도체디스플레이기술학회지
• /
• 제2권3호
• /
• pp.31-36
• /
• 2003

On this study, an E.E(End-Effector) for the 300 mm wafer transfer robot system is newly suggested. It is a mechanical type with $180^{\circ}$ rotating ranges and is composed of 3-point arms, two plate springs and single-axis DC motor controlled by microchip. To design, relationship between the gripping force and the wafer deformation is analyzed by FEM. By analytic results, the gripping force for 300 mm wafer is confirmed as 255~274 gf. From experimental results on gripping force, repeatable position accuracy and gripping cycle times in a wafer cleaning system, we confirmed that the suggested E.E was well designed to satisfiy on the required performance for 300 mm wafer transfer robot system.

• 반도체디스플레이기술학회지
• /
• 제2권4호
• /
• pp.23-26
• /
• 2003

The general users find difficulties in using ellipsometers. Thus, the object of this study is to construct an ellipsometer with simple operation principle. We developed an ellipsometer which does not require alignment and calibration before measuring sample. A basis structure model after rotating a compensator spectroscopic ellipsometry, the fixed incidence angle at $70^{\circ}$. This ellipsometer does not demand calibration, because the plane of incidence is not changed due to the novel sample holder structure. The results for various standard samples were compared with those from conventional RCSE to test the performance of this instrument. Also repeated measurements were performed to test the precision of the calibration coefficient in a plane of incidence fixed.

• 반도체디스플레이기술학회지
• /
• 제2권1호
• /
• pp.15-19
• /
• 2003

Spin etcher can process frontside and backside on the wafer, which is used for etching, stripping, cleaning and wafer reclamation. A new generation of spin etchers has been designed to meet 300mm wafer processing. The larger header and higher spin speed make vibration problem a severe problem in developing equipments. This study shows schematic process of solving practical vibration problems, where it is required to analyze the principal ca uses of vibration problem and find out the method of vibration reduction in spin etcher. The vibration under normal operation is measured in time domain and is analyzed in frequency domain. And modal parameters are obtained through modal test. Using the modal parameters from experiments, the model of finite element method is formulated. From diagnosis using many measurements and analyses, it can be shown that main cause of vibration is unbalance of head.

• 반도체디스플레이기술학회지
• /
• 제10권3호
• /
• pp.49-52
• /
• 2011

This paper shows the results of classical molecular dynamics modeling for the interaction between spherical nano abrasive and substrate in chemical mechanical polishing processes. Atomistic modeling was achieved from 3-dimensional molecular dynamics simulations using the Morse potential functions for chemical mechanical polishing. The abrasive dynamics was modeled by three cases, such as slipping, rolling, and rotating. Simulation results showed that the different dynamics of the abrasive results the different features of surfaces. The simulation concerning polishing pad, abrasive particles and the substrate has same results.

• 반도체디스플레이기술학회지
• /
• 제17권4호
• /
• pp.91-96
• /
• 2018

In this study temperature distribution and gas flow inside a planetary type reactor in which a number of satellites on a spinning susceptor were rotating were analyzed using numerical simulation. Effects of flow rates on gas flow and temperature distribution were investigated in order to obtain design parameters. The commercial computational fluid dynamics software CFD-ACE+ was used in this study. The multiple-frame-of-reference was used to solve continuity, momentum and energy conservation equations which governed the transport phenomena inside the reactor. Kinetic theory was used to describe the physical properties of gas mixture. Effects of the rotation speed of the satellites was clearly seen when the inlet flow rate was small. Thickness of the boundary layer affected by the satellites rotation became very thin as the flow rate increased. The temperature field was little affected by the incoming flow rate of precursors.

• 반도체디스플레이기술학회지
• /
• 제18권1호
• /
• pp.25-31
• /
• 2019

In this study, a new adhesion evaluating equipment and data processing methods were developed to overcome some limitations of existing evaluating equipment. Nano-diamond coated tool is a specimen of experiment. When applying frictional force and shear force on the specimen by a rotating polishing pad, delamination occurs at a moment. During each experiment, the vibration, load, and torque is obtained by accelerometer, loadcell and torque s+ kpensor. Frictional force and coefficient of friction are obtained by calculating torque and load. Based on FFT transformation, acceleration is processed and analyzed. As a result, the moment of delamination and the load at that time can be detected by the new developed equipment and measurement system. Finally, we call this load as an Adhesion force.

• 한국콘텐츠학회논문지
• /
• 제16권1호
• /
• pp.515-520
• /
• 2016

입체영상 시스템은 최근 교육, 3D 영화, 의료 영상 등 다양한 분야에 응용되고 있으나 실용화함에 있어 해결해야할 문제점도 남아있다. 입체영상 디스플레이는 실용화 단계에서 대량의 영상 데이터를 처리해야 하고 실시간 디스플레이를 위해 고효율 비젼 시스템을 설계해야 한다. 입체영상 디스플레이를 위한 스테레오 시스템에서는 움직임 벡터, 변위 벡터 및 오차영상이 전송되며 스테레오 영상 시퀀스를 복원하여 디스플레이를 하게 된다. 그러므로 효율적인 입체영상시스템 설계를 위한 핵심요소는 스테레오 영상간의 효율적인 정합과 강건한 비젼 시스템에 있다. 본 논문에서는 광학 플랫폼 위에 회전이 가능한 회전단과 수평이동이 가능한 단을 설계하고 카메라를 이용하여 순차적으로 스테레오 영상을 취득하여 정합함으로써 정확한 3D 정보를 추출할 수 있는 고효율 비젼 시스템을 제안한다. 제안한 입체영상 시스템 실험결과 간략화된 시스템 구조 보정을 통해 적은 계산량으로 입체영상 디스플레이를 위한 스테레오 정합에러를 최소화할 수 있었다.