• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.201-204
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• 1999

Polarization mode dispersion (PMD) restrict the bend-width of single mode optical filer, and it is important parameter in the optical fiber having long-length. Although fiber has perfect circular symmetry, fiber bending, twisting and laws governing manufacture cause additional Polarization mode dispersion. The effect of polarization mode dispersion in general single mode fiber of long length is discussed in this paper. Measurement of PMD with random mode coupling were conducted in two kind of fibers using different laws governing manufacture and interferometric method.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.145-150
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• 2007

Optical communication according to request of technology of communications and optical fiber to be full filed faster communication and pass over transmission capacity limit per unit area, per unit hour appeared, and this optical fiber acts the biggest role to influence performance of optical communication network. Optical fiber(PMF Polarization Maintaining Fiber) is used, and is used by electric field measurement, self-discipline measurement, sensor(Sensor) Department by high definition measure such as thermometry and storehouse component that use because make broad sense status and polarized light information in passageway and union with storehouse integrated circuit etc. that use broad sense interference developing could transmit in state that keep transmitting broad sense plane of polarization is polarized light existence. Also, research is developed by optical fiber for Coherent communication recently.

• 한국광학회지
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• 제14권3호
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• pp.224-229
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• 2003

2$\times$2 방향성 결합기와 단일모드 광섬유를 이용하여 무편광기를 구현하였다. 행렬식을 이용한 모의실험을 통해 편광도를 줄이는 방법을 이론적으로 설명하였고 이를 실험적으로 검증하였다. 0.05 nm 이하의 좁은 선폭을 가진 편광된 입력광원의 편광상태 변화에 대해 -20 dB의 출력 편광도를 얻을 수 있었다 광섬유 지연선의 길이를 광원의 가간섭 길이보다 충분히 길게 함으로써 입력광의 편광 변화에 의한 강도 잡음을 효과적으로 없앨 수 있음을 실험적으로 검증하였다.

• 한국광학회지
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• 제14권4호
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• pp.449-453
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• 2003

자이로스코프용 광대역폭 erbium 첨가 광섬유 광원에서 중심파장의 편광의존성을 억제하기 위하여 펌프광의 편광을 변조함으로써 스크램블링하는 방식을 사용하였다. 원통형 PZT에 광섬유를 감은 형태의 편광변조기에 적정진폭의 변조를 가함으로써 펌프광의 편광도(시간평균치)를 1.4%까지 낮출 수 있었다. 펌프 편광 스크램블러와 출력단 depolarizer를 함께 사용한 경우에 임의의 편광변화에 대한 광원의 중심파장 변화가 측정기의 측정한계(∼5 ppm) 이하로 관찰되었다.

• 대한기계학회논문집B
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• 제21권11호
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• pp.1509-1517
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• 1997

Charged and uncharged particle motions and collection characteristics around a bipolar charged rectangular shape electret fiber are studied numerically. Particle inertia, fluid drag, Coulomb force and polarization force are considered to predict the particle motion around the electret fiber. The effects of particle sizes, flow velocities, number of charges and polarities are also systematically investigated. For small size particles, the single fiber collection efficiency is greatly dependent on the charge polarity and the number of charges on a particle. However, particles larger than 5.mu.m do not show charging effect on collection efficiencies in the flow velocity ranges from 1.5 cm/s to 150 cm/s when the maximum charges are within +5 to -10. The results show that a strong electric field gradient at the corner of the bipolar charged fiber plays a very important role on collecting particles regardless of its charge polarity because of the polarization force. It also shows that the most penetrating particle size for a single electret fiber decreases as the flow velocity increases and the number of charges of a particle decreases.

• 대한전자공학회논문지
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• 제25권10호
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• pp.1158-1165
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• 1988

본 논문에서는 편광 유지 광섬유의 일종인 spun 광섬유의 고유 복굴절 및 자기 광학 효과에 의한 편광 특성을 이론적으로 해석하고 실험하였다. Spun 광섬유의 고유 복굴절을 나타내는 평광도는 최소 0.818 이상으로 측정되었고 입력 편광각에 대한 출력 편광각의 변화는 9$^{\circ}$ 이내로 측정되어 단일 모드 광섬유의 편광 특성에 비해 spun 광섬유가 매우 우수한 편광 유지 특성을 갖음을 알 수 있었다. Spun 광섬유로 구성한 전류 측정 시스템은 솔레노이드로 인가된 0,000A/m까지의 자계 강도를 선형적으로 측정 가능 하였다.

• Journal of the Optical Society of Korea
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• 제20권6호
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• pp.716-721
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• 2016

A single-and dual-wavelength switchable polarized Yb-doped double-clad fiber laser around 1120 nm based on a pair of fiber Bragg gratings (FBGs) is demonstrated. The polarization-maintaining (PM) linear cavity is composed of a double clad PM Yb-doped fiber (YDF) and a pair of PM FBGs. The laser can operate in stable dual-wavelength or wavelength-switching modes due to the polarization hole burning (PHB) and the spatial hole burning (SHB) enhanced by the PM linear cavity. In dual-wavelength operation, the two orthogonally polarized wavelengths are centered at 1118.912 nm and 1119.152 nm, with an interval of 0.24 nm and a signal to noise ratio (SNR) of 35 dB. The maximum output power is 14.67 W when the launched LD pump is 24 W corresponding to an optical efficiency of 61.1%. The lasing lines switchover may be realized by adjusting the polarization controller (PC) fitted in the cavity. The two single-wavelengths are 1118.912 nm and 1119.152 nm. When the injected LD pump is 24 W, the highest output powers are 7.68 W and 8.64 W corresponding to optical efficiencies of 32% and 36% respectively. The spectral linewidth of the lasing lines are 0.075 nm and 0.07 nm, and the average numerical values of PER aredB and 19.9 dB, respectively.

• 한국조명전기설비학회지:조명전기설비
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• 제5권1호
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• pp.31-39
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• 1991

편광유지 광섬유의 한 종류인 저 복굴절 광섬유의 고유복굴절 및 자기광학 효과에 의한 편광 특성을 이론적으로 해석하고 실험하였다. 일반 단일모드 광섬유에 비해 편광유지 특성이 양호하게 나타났으며, 실험결과 본 실험에 사용된 광섬유(길이: 68.28cm, 163.72cm, 139.52cm)의 편광도는 0.818이상으로 특정되었다. 입력 편광각에 대한 출력 편광각의 변화는 $9^{\circ}$이하로 측정되었다. 자계 측정 실험결과 10kAT까지의 자계 강도를 선형적으로 측정할 수 있었으며 최대 오차는 4kTA에서 1.95%였다.

• 조명전기설비학회논문지
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• 제26권6호
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• pp.8-15
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• 2012

In this paper, we investigated possible optical parameters causing deviation of experimentally observed output spectra from theoretically predicted results in a high-order fiber comb filter based on a polarization-diversity loop configuration. They include wavelength dependency of half-wave plates (HWPs) inserted in the filter for wavelength switching and the modal birefringence of single-mode fibers (SMFs) with which optical components comprising the filter are connected. In order to consider the effect of the modal birefringence of the SMF on a filter performance, it is modeled as a low birefringence fiber with an arbitrary orientation angle and birefringence. It is found from the simulation results that the modal birefringence of SMFs strongly affects the spectral characteristics of the filter and decreases the extinction ratio of the filter, compared with the wavelength dependency of HWPs. In particular, it is also confirmed that the spectral deviation and asymmetric distortions of side-lobes in narrow band transmission spectra result mainly from the modal birefringence of SMFs.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2456-2458
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• 1999

The polarization mode dispersion (PMD) that restricts the transmission bandwidth was investigated in standard long single mode fiber which optimized at 1.3${\mu}m$. Although fiber has perfect circular symmetry, each optical fiber has different refractive index profiles. The investigation of PMD with random mode couplings were conducted in three kinds of fiber by the time-domain interferometric method. By using two manufacturing methods, MCVD(Modified Chemical Vapor Deposition) method and VAD(Vapor Phase Axial Deposition) method, the property of mechanical asymmetric lateral pressure, bending and twisting induced polarization mode dispersion were measured. The concatenated optical fibers were compared with other types.