• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2004년도 추계총회 및 연구발표회 초록집
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• pp.95.4-95.4
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• 2004

• 한국광학회지
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• 제15권1호
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• pp.28-33
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• 2004

상부 도파로와 중간 결합층이 적층된 단일모드 광섬유를 기본구조로 하는 측면 연마 광섬유 결합기를 상호 광 결합이 일어나는 영역을 다층막 도파로로 등가화하여 결합 효율을 해석하였다. 다층막 구조에서 중간 결합층의 유무에 따른 반사도를 계산하여 상부 도파로의 굴절률의 함수로 도시하였고, 상부 도파로의 굴절률이 광섬유 코어의 굴절률보다 클 경우 중간 결합층의 조건에 의해서 광 결합이 증가되어짐을 보였다. 리튬나오베이트를 상부 도파로로 가지는 결합기의 실험결과를 톤해 이론적 해석의 타당함을 보였고 계산 결과와 일치함을 보였다.

• E2M - 전기 전자와 첨단 소재
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• 제9권3호
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• pp.298-303
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• 1996

A double diffusion technique is developed to enhance the effective mode index of optical waveguides in $LiTaO_3$. It consists of Zn diffusion from the vapor phase at relatively low temperatures (750->$800^{\circ}C$), into waveguides initially produced by Ti indiffusion at higher temperature (1150->$1200^{\circ}C$). Both X- and Z-cut substrates are investigated. A model that combines profiles of both diffusion is formulated to calculate the expected effective index values for planar waveguides. Good agreement is found between experimental results and model predictions which assume that the initial Ti profile is not affected by the lower temperature Zn diffusion. Effective index enhancements as high as 0.005 and 0.003 are obtained by this method for the fundamental extraordinary and ordinary modes, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.390-390
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• 2008

In this paper, we have designed and fabricated optical waveguides based on the Mach-Zehnder Interferometer (MZI) for application to sensor. The evanecent-wave sensor based on the MZI principle has sufficiently high sensitivity to measure the change of the refractive index on surface of a waveguide. The waveguides were optimized at a wavelength of 1550 nm and fabricated according to the design rule of 0.45 delta%, which is the difference of refractive index between the core and clad. The fabrication of MZI optical waveguides was performed by a conventional Planar Lightwave Circuit (PLC) fabrication process. The fabricated MZI optical waveguide device was measured. According to the measurement result, the insertion loss of MZI optical waveguide device was below 3.5 dB and the polarization dependent loss (PDL) was within 0.1dB. In addition, we analyzed optical properties of MZI sensor according to the refractive index change of the sensor arm.

• 대한전기학회논문지
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• 제45권1호
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• pp.146-158
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• 1996

The WKB method has been widely used in evaluating of the propagation characteristics of planar waveguides with graded-index profiles. This method, however, yields large errors when a turning point is near or at the discontinuity in the presence of the index discontinuity or index slope discontinuity. Especially, in the case of a truncated-index profile, this phenomenon appears more clearly in the low-order modes and near the cutoff regions. The MWKB method is introduced to reduce these inherent errors of the conventional WKB method. The MWKB method is based on both the linearization of the index profile from an index discontinuity and the introduction of a virtual turning point. It is noticed that the b-v curves obtained by the MWKB method agree well with those of the finite-difference method, and that the phase shift at a turning point depends on both the index profile and its propagation constant. (author). refs., figs.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.37-39
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• 1994

We have investigated the characteristics of planar optical waveguides formed by silver ion-exchange. Experimental values of the effective indices of guided modes were obtained by measuring the synchronous angles of strongest coupling. Definition of an effective diffusion constant leads to the mode-dispersion curves applicable over a wide range of fabrication conditions. In order to compare experimental and theoretical results, We have plotted each mode index of a wide range of fabrication conditions.

• 한국광학회:학술대회논문집
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• 한국광학회 1996년도 Advance Program of 13th optics andquantum Electronics conference, 1996제13 회 광학 및 양자전자 학술 발표회 논문 요약집
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• pp.62-62
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• 1996

• Journal of electromagnetic engineering and science
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• 제11권2호
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• pp.97-104
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• 2011

A planar slotted waveguide array antenna has been designed at 9.37 GHz for X-band radar applications. The antenna consists of multiple branchline waveguides with broadwall radiating shunt slots and a main waveguide to feed the branch waveguides through a series of inclined coupling slots. The antenna feed point is located at the center of the main waveguide. Element weights in the array have been calculated bysampling a continuous circular Taylor aperture distribution at the 25 dB sidelobe level in both the E and Hplanes. A commercially available electromagnetic (EM) simulation tool has been used to characterize the individual isolated slot and that data hassubsequently been used to design the planar array. The array is finally analyzed in a CST Microwave studio and the measured and simulated results have been found to be in good agreement.

• 대한전자공학회논문지
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• 제25권3호
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• pp.343-351
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• 1988

Planar optical waveguides are fabricated on a Y-cut LiNbO3 single crystal substrate by Ti indiffusion method. From data measured by the bright M-line spectroscopy, refractive index profiles are reconstructed by WKB approximation method. Then, single strip, X-crossing strip, and Y-brinch strip optical waveguides are fabricated on X-cut LiNbO3 single crystal substrate, with waveguide patterns made by the laser beam direct writing method. And their near-field intensity profiles are observed after coupling the light to the waveguide edges.

• 한국결정성장학회지
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• 제10권4호
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• pp.297-301
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• 2000

H와 Li의 양자교환법에 의해 평면도파로와 channel도파로를 $LiNbO_3$단결정 기판위에 구현하였다. 양자원으로 피로인산을 사용하였고 평면도파로의 모드들에 대한 유효굴절률을 측정하였으며 반응시간과 반응온도로부터 광도파로의 깊이와 계단형 형태의 굴절률 변화에 대한 식을 구하였다. 이 식에서 구한 단일모드 도파 조건으로 channel 도파로를 제작하였고 입사광의 제한 효과를 관찰하였다.