• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.396-397
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• 2009

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.501-502
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• 2006

• Korean Journal of Optics and Photonics
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• v.10 no.3
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• pp.248-253
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• 1999

In this paper, we have investigated a fiber type active coupler which utilizes the mode coupling between the side polished single mode optical fiber and the active multimode planar waveguide. The proposed device can be used for not only tunable wavelength filter or optical intensity modulator but also a tool for measuring optical properties of guiding material such as refractive index, birefringence, electro-optic coefficient, and thermo-optic coefficient. We gave designed and optimized a coupler structure using the BPM and fabricated the device using thermo-optic polymer as active planar waveguide overlay. The device showed that insertion loss was less then 0.5 dB, extinction ratio was -13 dB at the resonance wavelength, and the wavelength tunablity due to thermo-optic effect was -1.5 nm/$^{\circ}C$. The active coupler using thermo-optic effect can be used as a wavelength tunable filer, an optical intensity modulator and an optical sensor. pulses that are subsequently compressed by a dispersive optical fiber. Experimental results show that $sech^2$ shape pulses with a pulse width of ~14 ps and a time bandwidth product of ~0.34 are successfully generated at 10 GHz repetition rate. In contrast to other methods, such as higher order soliton compression, this approach does not depend on the optical power and thus shows promise for application to low-power lasers.

• Korean Journal of Optics and Photonics
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• v.5 no.2
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• pp.311-318
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• 1994

We fabricated fiber-optic polarizers utilizing polarization selective mode coupling between the guided mode of a fiber and the surface plasmon mode supported by a thin aluminium film deposited on the polished side of a fiber. AI thin films with various thicknesses were coated onto the 633 nm, 830 nm, 1.3 fJITI single mode fibers. The maximum extinction ratio was higher than 30 dB for most of the samples and the best result was 42 dB at 90 A film thickness, with 1.3 fJITI single mode fiber. The insertion loss ranged from 0.2 dB to 1.5 dB.1.5 dB.

• Journal of Sensor Science and Technology
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• v.10 no.3
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• pp.156-162
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• 2001

Novel pressure sensor using the resonance wavelength shift of single mode fiber-to-planar waveguide coupler, was demonstrated. It is found that the resonance wavelength shift due to refractive index variation of polymers by pressure occurs and its sensitivity depends on materials. We adopted symmetric structure of planar waveguide and remove the polarization dependence which is inevitable with side-polished fiber. AZ4562, AZl512 and THB-30 are used as planar waveguide materials and the resonance wavelength shifting by pressure was shown -0.008um/bar, 0.033nm/bar and 0.16nm/bar, respectively.

• Korean Journal of Optics and Photonics
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• v.15 no.6
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• pp.591-596
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• 2004

In this paper, a photonic RF true-time delay based on a partially side-polished fiber Bragg grating with heating electrode has been proposed and fabricated. It features continuous voltage-controlled operation, requiring no mechanical perturbation and no moving parts. For an RF signal carried over an optical signal, the time delay has been obtained by controlling the voltage applied to the electrode and thus adjusting its reflection positions from the fiber grating via the thermooptic effect. The achieved time delay is about 100 ps with the electrical power consumption of 280 mW.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.246.1-246.1
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• 2007

• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.50-51
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• 2002

측면 연마된 광섬유 표면 위에 새로운 물질층을 형성시킨 후 광섬유 모드의 소산장(evanescent field) 결합을 유도하여 다양한 능동 및 수동 광섬유로 응용이 가능하다. 광섬유를 연마하기 위하여 쿼츠에 형성된 홈에 광섬유를 에폭시로 고정시키고 쿼츠와 함께 광섬유 클래딩을 연마하는 방법이 잘 알려져 있다. 이러한 방법은 측면 연마된 광섬유를 연마하는데 다소 긴 시간이 필요하다. 본 논문은 광섬의 클래딩을 연마휠로 제거하는 기법을 소개하고 연마된 광섬유의 클래딩 위에 금속이나 유전체층을 결합하여 기능성 광섬유 소자를 제작할 수 있음을 보인다. (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.18-19
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• 2003

측면 연마 광섬유 결합기는 비록 제작 공정이 다소 복잡하지만 다양한 응용이 가능하기 때문에 많은 연구가 진행 되어 왔다. 특히 최근에는 광센서나 초고속 광통신망에 편광 유지 광섬유를 이용한 광학소자의 필요성이 증가 하고 있다. 본 논문은 얇은 중간 금속 층을 가지는 측면 연마 편광 유지 광섬유 결합기를 이용한 편광 분리기에 관한 실험 연구 결과를 보고한다. (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2002.11a
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• pp.182-183
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• 2002