Investigation on the Dispersion Characteristics in Optical Fiber Telecommunication

Xiaofang Liu,Xiaohong Fan 보안공학연구지원센터 2014 International Journal of Future Generation Communi Vol.7 No.6

Dispersion is widely existed in the optical fiber. The reason is various, such as material dispersion, waveguide dispersion, mode dispersion, and so on. It will lead to the signal waveform distortion and pulse broadening and then limit the transmission capacity and bandwidth in the optical fiber. With the rapid development, transmission rate can reach even hundreds of Gb/s, and it may lead to many problems. Correspondingly, compensation methods have been paid much attention, and there are also many methods proposed for the compensation. However, we should know the characteristics of the dispersion in order to get compensation algorithms with much higher efficiency. Optical fiber systems with better performance will be designed and manufactured. In this paper, appropriate methods are adopted to analyze the photonic crystal fiber. With the adjusting of the structure parameters, we can design a highly nonlinear photonic crystal fiber with different dispersion characteristics. We study the characteristics of the dispersion of optical fiber communication. According to the analysis to obtain the dispersion characteristics of optical fiber under different parameters.

Investigation on the Dispersion Characteristics in Optical Fiber Telecommunication

Ni Yan Rong,Min Ru 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.4

Dispersion is widely existed in the optical fiber. The reason is various, such as material dispersion, waveguide dispersion, mode dispersion, and so on. It will lead to the signal waveform distortion and pulse broadening and then limit the transmission capacity and bandwidth in the optical fiber. With the rapid development, transmission rate can reach even hundreds of Gb/s, and it may lead to many problems. Correspondingly, compensation methods have been paid much attention, and there are also many methods proposed for the compensation. However, we should know the characteristics of the dispersion in order to get compensation algorithms with much higher efficiency. Optical fiber systems with better performance will be designed and manufactured. In this paper, appropriate methods are adopted to analyze the photonic crystal fiber. With the adjusting of the structure parameters, we can design a highly nonlinear photonic crystal fiber with different dispersion characteristics. We study the characteristics of the dispersion of optical fiber communication. According to the analysis to obtain the dispersion characteristics of optical fiber under different parameters.

Optical Encryption and Information Authentication of 3D Objects Considering Wireless Channel Characteristics

이인호,조명진 한국광학회 2013 Current Optics and Photonics Vol.17 No.6

In this paper, we present an optical encryption and information authentication of 3D objects consideringwireless channel characteristics. Using the optical encryption such as double random phase encryption(DRPE) and 3D integral imaging, a 3D scene with encryption can be transmitted. However, the wirelesschannel causes the noise and fading effects of the 3D transmitted encryption data. When the 3D encrypteddata is transmitted via wireless channel, the information may be lost or distorted because there are a lotof factors such as channel noise, propagation fading, and so on. Thus, using digital modulation andmaximum likelihood (ML) detection, the noise and fading effects are mitigated, and the encrypted datais estimated well at the receiver. In addition, using computational volumetric reconstruction of integralimaging and advanced correlation filters, the noise effects may be remedied and 3D information may beauthenticated. To prove our method, we carry out an optical experiment for sensing 3D information andsimulation for optical encryption with DRPE and authentication with a nonlinear correlation filter. To thebest of our knowledge, this is the first report on optical encryption and information authentication of 3Dobjects considering the wireless channel characteristics.

안경원을 대상으로 한 경영관리 특성이 경영성과에미치는 영향 연구

유민정,심상현 한국안광학회 2013 한국안광학회지 Vol.18 No.4

Purpose: We divide management characteristics into business strategy, operation management, information management, marketing, asset management. Also this will show effect on business performance according to management characteristics. Methods: For two months, from August to October, a manager (include an executive) participated in individual questionnaires. And the SPSS v14.0 was applied to analyze data of this study. Results: This study has shown that the management characteristics have an effect on the finance and satisfaction performance. In particular, the ‘business strategy’ and ‘marketing’ of management characteristics were important factors that affects finance performance and the ‘business strategy’, ‘marketing’ and ‘operation management’ were important factors that affects satisfaction performance. Conclusions: Consequently through this result, we should make an efforts to ‘business strategy’ and ‘marketing’ of management characteristics. 목적: 안경원을 운영하는데 있어 경영전략, 정보관리, 마케팅, 운영관리, 자금관리 등의 경영관리 특성이 안경원의경영성과에 미치는 영향을 알아보고 각 요인 중 중요요인과 경영관리 특성에 따른 비교분석을 통해 안경원 관리 및운영에 필요한 정보를 제공하고자 한다. 방법: 2011년 8월부터 10월까지 약 2개월 동안 안경원 관리자(경영자 포함)를대상으로 설문지를 배포하여 SPSS v 14.0 통계 패키지 프로그램을 활용하여 분석하였다. 결과: 안경원의 경영관리특성에 따라 재무성과 및 만족성과가 다르게 나타났으며 특히 안경원의 재무성과 향상에는 경영전략, 마케팅 특성이, 만족성과 향상에는 경영전략, 마케팅, 운영관리 특성이 가장 중요한 요인으로 나타났다. 결론: 이 결과에 따르면안경원 경영성과 향상을 위해서는 경영관리 특성 중 하위요인 중 경영전략, 마케팅 특성을 특히 고취시키기 위해노력해야 할 것이다.

Manufacture of microscale random pattern using indentation machining technology

Je-Ryung Lee,Seung Hwan Moon,Tae-Jin Je,Doo-Sun Choi,Hwi Kim,Eun-chae Jeon 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.7 No.6

The display industries recently demand new microscale dot-type patterns for thinner and brighter displays with high energy efficiency, which are randomly distributed with irregular separation distances and have uniform optical characteristics. We developed a new program to generate the coordinates of the controlled microscale random patterns considering their diameter and the distance to the nearest pattern for preventing overlap of each pattern. Then the microscale random patterns were machined on a metal mold using the indentation machining which is a simple and low-cost machining method. We decreased the total machining time by the optimization of machining order of the random patterns. The coordinates, the diameter and the fi ll-factor of the machined patterns by the indentation machining were much consistent to the designed values. The controlled microscale random patterns had uniform optical characteristics over all areas of the manufactured optical fi lm. Moreover, if optical films have the same diameters and fi ll-factor, they showed the same optical characteristics even they have totally different coordinates of random microscale patterns. This technology is expected to reduce the number of the optical films and the light sources in the display, which can save much energies.

형광증백제가 종이 셀룰로오스의 화학적 열화특성에 미치는 영향

이재훈,최경화,조병욱 한국펄프·종이공학회 2015 펄프.종이기술 Vol.38 No.1

This study was conducted to investigate the effects of optical brightening agents (OBA) on the chemical degradation characteristics of paper cellulose during humid heating aging. Three different types of OBAs were applied to a filter paper by dipping it in OBA solutions whose concentrations were controlled to 1% and 2%. The filter papers with an OBA were artificially aged at 80℃ and 65% RH, and the changes in pH of paper and viscosity of cellulose were evaluated. Their functional groups were also analyzed by ATR-FTIR (attenuated total reflectance fourier transform infrared spectroscopy). It was found that OBAs influenced the chemical degradation of paper cellulose during humid heating aging. Higher concentration of OBA solutions accelerated the degradation of paper cellulose. Especially, after aging for 12 days, the paper cellulose treated with the tetra-type OBA were the most significantly aged among the three types of OBAs. It was assumed that pH of OBA solutions affected the aging characteristics.

Hardness and Abrasion Resistance Characteristics of Poly(ethylene terephthalate) Films without and with Hard and Adhesive Coatings

Zi Jia Low,Jia Chyi Wong,Kuan Hoon Ngoi,Chin Hua Chia,김현중,김홍철,이문호 한국고분자학회 2021 Macromolecular Research Vol.29 No.3

In this study, we reports the first quantification details of the pencil hardness, eraser abrasion resistance and steel wool abrasion resistance of optically-transparent and biaxially-oriented poly(ethylene terephthalate) (PET) films in various thicknesses before and after hard coating (HC) and/or optically clear adhesive (OCA) coating. Surprisingly, the PET base films were determined to exhibit unrealistically very low hardness and abrasion resistances although their stress-strain behavior followed a ductile and tough plastic nature as a high performance engineering plastic: the pencil hardness was only ≤9B even at a low loading force, 0.100 kgf, and the onset loading force to cause scratches was far below 0.013 kgf in both eraser and steel wool abrasions. These collectively confirmed that, without surface protections, PET base films are not suitable for any advanced applications. Such the low hardness and poor abrasion resistances could be improved substantially by only thin HC coating of di(trimethylolpropane) tetraacrylate (HC-a, an ultraviolet curable acrylic resin). In addition, the OCA coating based on an acrylic copolymer adhesive provided adhesion function to the PET films, showing excellent adhesion strength onto chemically-toughened glass. However, the OCA layer causes cushioning effect because of its easy plastic deformation nature, making negative impact on the hardness and abrasion resistance performances of the PET film. Thus, the OCA coating should be thinned until retaining good adhesion to adherends. Overall, PET films coated with HC and/or OCA are suitable for advanced applications in various fields including smart phones, foldable phones, and flexible display devices.

형광증백제가 종이 셀룰로오스의 화학적 열화특성에 미치는 영향

이재훈(Jae-Hun Lee),최경화(Kyoung-Hwa Choi),조병욱(Byoung-Uk Cho) 한국펄프·종이공학회 2015 펄프.종이기술 Vol.47 No.6

This study was conducted to investigate the effects of optical brightening agents (OBA) on the chemical degradation characteristics of paper cellulose during humid heating aging. Three different types of OBAs were applied to a filter paper by dipping it in OBA solutions whose concentrations were controlled to 1% and 2%. The filter papers with an OBA were artificially aged at 80℃ and 65% RH, and the changes in pH of paper and viscosity of cellulose were evaluated. Their functional groups were also analyzed by ATR-FTIR (attenuated total reflectance fourier transform infrared spectroscopy). It was found that OBAs influenced the chemical degradation of paper cellulose during humid heating aging. Higher concentration of OBA solutions accelerated the degradation of paper cellulose. specially, after aging for 12 days, the paper cellulose treated with the tetra-type OBA were the most significantly aged among the three types of OBAs. It was assumed that pH of OBA solutions affected the aging characteristics.

A Study on Analysis of Integrated-Optic Wavelength Filter

Kim, Jong-Heon 광운대학교 신기술연구소 1996 신기술연구소논문집 Vol.25 No.-

광 필터 특성을 해석하기 위해서 정방향 및 부방향 결합기로 분류되는 격자 보조 광 도파로 결합기에서의 파장 선택도를 행렬 방법을 사용하여 고찰 하였다. 도파로 결합기를 사용한 광 필터의 동작에 영향을 주는 기본 설계 파라미터들에 관하여 논하였으며 행렬 방법에 의한 결과와 결합 모드 이론에 의한 결과를 비교하였다. The wavelength selectivity in grating-assisted optical waveguide couplers -classified as a codirectional and a contradirectional coupler- is studied by a matrix method to analyse optical filter characteristics. The influence of fundamental design parameters on the performances of the optical filters by waveguide couplers is discussed, and the results by the matrix method are compared with those by the coupled mode theory.

에틸헥실아크릴레이트/하이드록시에틸아크릴레이트 광 접착 코팅 물성

김태이(Taeyee Kim),김동복(Dongbok Kim),강호종(Ho-Jong Kang) 한국고분자학회 2017 폴리머 Vol.41 No.2

광중합에 의하여 2-ethylhexyl acrylate(2-EHA)/2-hydroxyethyl acrylate(2-HEA) 광 접착 수지를 합성하고 2-HEA 첨가가 광중합과 코팅특성에 미치는 영향을 살펴보았다. 수지에 2-HEA 양이 증가할수록 광중합 속도가 증가되어 광 조사 시간에 따른 전환율이 증가됨을 알 수 있었다. 수지 코팅에 적절한 낮은 전환율에서 광조사 시간 및 HEA 함량 증가에 따라 분자량 분포가 급격이 증가되며 이는 코팅성 향상에 도움이 되는 점도 감소를 초래함을 확인하였다. 광 접착 수지의 코팅특성은 수지 점도와 매우 밀접한 관계가 있으며 8~11% 전환율을 갖는 수지가 코팅두께 균일성을 가지며 동시에 코팅성이 우수함을 알 수 있었다. 2-Ethylhexyl acrylate (2-EHA)/2-hydroxyethyl acrylate (2-HEA) optically clear resin (OCR) was synthesized by photopolymerization, and the effect of 2-HEA on photopolymerization was investigated with their coating characteristics. 2-HEA caused the acceleration of photopolymerization; as a result, the conversion could be controlled by UV exposure time as well as the amount of 2-HEA in the resin. The resin having low conversion suitably was needed for good coating characteristics, and low viscosity was found due to the increase of molecular weight distribution by increasing 2-HEA. It was found that coating characteristics were closely related to the viscosity of resin, and appropriate conversion was 8~11% that showed the uniform coating thickness with good coating ability.