• 한국정밀공학회지
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• 제29권12호
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• pp.1376-1381
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• 2012

Optical devices are used extensively in the field of information network. Increasing demand for optical device, optical interconnection has been a important issue for commercialization. However many problems exist in the interconnection between optical device and optical fiber, and in the case of the multi-channel, problems of the optical alignment and optical array arise. For solving the alignment and array problem of optical device and the optical fiber, we fabricated fiber alignment and array by using imprint technology. Achieved higher precision of optical fiber alignment and array due to fabricating using imprint technology. The silicon stamp with different depth was fabricated using the conventional photolithography. Using the silicon stamp, a nickel stamp was fabricated by electroforming process. We conducted imprint process using the nickel stamp with different depth. The optical alignment and array by fabricating the patterns of optical device and fiber alignment and array using imprint process, and achieved higher precision of decreasing the dimensional error of the patterns by optimization of process. The fabricated optical interconnection of PLC device was measured 3.9 dB and 4.2 dB, lower than criteria specified by international standard.

• 전자공학회논문지A
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• 제32A권9호
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• pp.128-134
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• 1995

A fiber-optic temperature sensor utilizing an optical absorption device (InP) was fabricated. The spectrum of transmitted light through an InP device was obtained at the three temperatures(249 K, 369 K). A stabilized LED(light emmiting diode) driver, photoreceiver, and signal proocessing electronics were designed. An intensity referencing technique was adopted in order to minimize the fluctuation of output signal due to external pertubation of the transmitting optical fiber. The optical absorption edge of the InP device moves to longer wavelength at a rate of 0.42 nm / K, and energy gap of InP is 1.35 eV at room temperature. From these results, it is concluded that the InP device has temperature dynamic range of 300 K with LED of center wavelength of 940nm and spectral width of 50nm. The designed fiber-optic temperature sensor system showed good linearity within the temperature range from -30$^{\circ}C$ to + 150$^{\circ}C$.

• 전기학회논문지
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• 제56권10호
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• pp.1820-1822
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• 2007

In this paper we fabricated a fiber device composed of cascaded long-period fiber gratings between which a birefringent erbium-doped fiber was inserted and proposed its application as a polarization-controlled interleaved signal gating fiber device. Because the core and cladding modes of the fabricated fiber device have polarization-dependent phase difference due to the birefringence of the erbium-doped fiber, its interference spectrum can be modulated by varying the input polarization.

• 한국광학회지
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• 제16권1호
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• pp.99-102
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• 2005

광섬유 링 레이저의 출력파장 가변을 위해서 신뢰성있는 새로운 스트레인 인가장치를 제작하고 이 장치를 이용하여 파장가변 광섬유 링 레이저를 구현하였다. 제작된 광섬유 링 레이저의 출력파워는 -12 dBm이었으며, 선폭은 0.05 nm이었다. 새로운 스트레인 인가장치를 이용하여 광섬유에 8000 $\mu$ strain을 인가하였을 때 광섬유 링 레이저의 출력파장은 약 10 nm 가변되는 것을 확인 할 수 있었다.

• 한국광학회지
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• 제16권3호
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• pp.191-195
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• 2005

압력이 인가되는 지점에만 장주기 광섬유 격자가 형성되는 광섬유 소자를 제작하였고, 제작된 소자의 특성을 조사하였다. 제작된 소자는 $720\;{\mu}m$ 주기의 격자가 윗면에 형성되어 있는 60 cm 길이의 금속막대와 고무덮개로 구성되어 있으며, 압력이 인가될 때에 압력이 인가된 지점에만 장주기 광섬유 격자가 형성되었고 인가된 지점에 관계없이 동일한 투과특성을 가지는 장주기 광섬유 격자들이 형성되었다. 그리고 제작된 소자의 특성측정을 통하여 무게를 측정할 수 있는 광섬유 로드(Load)센서로 사용 가능함을 보여 주었다.

• Investigative Magnetic Resonance Imaging
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• 제25권4호
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• pp.218-228
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• 2021

Due to their high degree of freedom to transfer and acquire light, fiber optics can be used in the presence of strong magnetic fields. Hence, optical sensing and imaging based on fiber optics can be integrated with magnetic resonance imaging (MRI) diagnostic systems to acquire valuable information on biological tissues and organs based on a magnetic field. In this article, we explored the combination of MRI and optical sensing/imaging techniques by classifying them into the following topics: 1) functional near-infrared spectroscopy with functional MRI for brain studies and brain disease diagnoses, 2) integration of fiber-optic molecular imaging and optogenetic stimulation with MRI, and 3) optical therapeutic applications with an MRI guidance system. Through these investigations, we believe that a combination of MRI and optical sensing/imaging techniques can be employed as both research methods for multidisciplinary studies and clinical diagnostic/therapeutic devices.

• 마이크로전자및패키징학회지
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• 제19권4호
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• pp.13-18
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• 2012

By the need for high-speed data transmission in PCB, the studies on the optical PCB has been conducted with optical interconnection and its packaging technology. Particularly, the polymer-based optical interconnection has been extensively studied with the advantages such as cost-effective and ease of process. For high-efficiency and passive alignment, the studies were performed using the 45 degree mirrors, MT connector, and etc. In this work, integrated PLC device and fiber alignment array block was fabricated by using imprint technology to solve the alignment and array problem of optical device and the optical fiber. The fabricated integrated block for optical interconnection of PLC device has achieved higher precision of decreasing the dimensional error of the patterns by optimization of process and its insertion loss has an average value of 4.03dB, lower than criteria specified by international standard. In addition, a optical waveguide with built-in lens has been proposed for high-efficiency and passive alignment. By simulation, it was confirmed that the proposed structure has higher coupling efficiency than conventional no-lens structure and has the broad tolerance for the spatial offset of optical waveguide.

• 한국광학회:학술대회논문집
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• 한국광학회 1999년도 제16회 광학 및 양자전자 학술발표회Proceedings of 16th Optics and Quantum Electronics Conference, 1999
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• pp.116-117
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• 1999

Optical fiber networks for microwave signal processing have been investigation . Theoretical and experimental results are presented in Z-shaped Double-Coupler Optical Resonator. The use of Mason's rule to calculate transfer functions greatly simplified the analysis in our model. A good comparison between modelling and experiment is presented.

• 한국광학회지
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• 제18권4호
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• pp.280-285
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• 2007

다중모드 광섬유 테이퍼(taper)를 이용하여 레이저와 광섬유 혹은 두 개의 서로 다른 광섬유 사이의 효과적인 광결합을 위한 모드 크기 변환기를 제안하고 구현하였다. 이 소자의 입력 단은 다중 모드 구조이고 출력단은 단일 모드 구조이다. 소자의 구조 및 광원과 소자사이의 결합 조건이 결합 효율에 미치는 영향을 이론적으로 분석하였다. 이론적 결과는 제안된 소자가 가우시안 빔을 단일모드 광섬유로 거의 손실 없이 결합할 수 있는 것을 보였다. 제안된 소자를 두 개의 마이크로 토치가 부착된 장비를 이용해 제작하였다. 실험 결과 제작된 다중모드광섬유 테이퍼를 통해 $50\;{\mu}m$ 빔 크기를 가지는 가우시안 빔을 단일모드 광섬유로 효과적으로 결합할 수 있는 것을 보였다. 소자의 삽입 손실은 1.3 dB였다.

• Journal of Electrical Engineering and Technology
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• 제1권4호
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• pp.546-549
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• 2006

In this paper the neuron operation based on Brillouin-active fiber in optical fiber is described. The inherent optical feedback by the backscattered stokes wave in optical fiber leads to instabilities in the form of optical chaos. Controlling of chaos induced transient instability in Brillouin-active fiber is implemented with Kerr nonlinearity having a non-instantaneous response in network systems. The controlling chaotic instabilities can lead to multistable periodic states; create optical logic 'on' or high level '1' or 'off', or low level '0'. It is theoretically possible to apply the multi-stability regimes as an optical memory device for encoding and decoding series and complex data transmission in optical systems.