• 한국광학회:학술대회논문집
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• 한국광학회 2006년도 동계학술발표회 논문집
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• pp.305-306
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• 2006

• 센서학회지
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• 제13권3호
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• pp.207-212
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• 2004

We have investigated the optical characteristics of a directional coupler made of a side-polished polarization maintaining fiber in contact with a multimode planar waveguide and its applications as sensors. A device structural condition to achieve the polarization insensitive wavelength response has been presented. The fabricated devices revealed a superior immunity to the bending and the deformation of PM fibers in the input section. It is experimentally shown that the proposed device is suitable for a remote fiber sensor.

• 한국광학회지
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• 제10권5호
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• pp.419-423
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• 1999

측면 연마된 단일모드 광섬유와 다중모드 폴리머 평면도파로 사이의 소산장 결합을 이용한 광필터를 제작하고 그 특성을 측정하였다. 소자의 편광의존성을 줄일 수 있는 방법 제안하였으며 실험으로 검증하였다. 그리고 광필터의 공진파장과 여과 깊이는 평면도파로의 두께와 연마깊이로서 적절히 선택할 수 있음을 실험으로 보였다. 광섬유 연마과정, 폴리머 평면도파로 제작 등을 포함한 소자제작 공정을 소개하였다. 제작된 광필터의 3㏈대역폭은 15nm, 삽입손실은 0.2㏈, 편광에 따른 공진 파장의 차이는 2nm 이하였다. 그리고 주위온도에 의한 공진파장의 이동거리는 -0.35nm/$^{\circ}C$로 측정되었다.

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 동계학술발표회 논문집
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• pp.385-386
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• 2009

• International Journal of Aeronautical and Space Sciences
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• 제12권2호
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• pp.175-178
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• 2011

An optical fiber-based beam width measurement technique is presented. The proposed system can be applied to the optical fiber industry in applications such as lensed fiber, optical fiber based laser beam source, and fiber optic sensor. The measurement system is composed of optical fiber, which is used as a transceiver, and a single grating panel which consists of a multi-reflection area with an even non-reflection area. The grating panel is used to vary the reflected light. When the widths of the reflection area and non-reflection area are larger than the optical beam width, the reflected light is varied at the interface between the reflection area and the non-reflection area by the movement of the grating panel. Experiments were conducted in order to verify the feasibility of the proposed technique. Multi-mode fiber combined with a collimator was selected as an emitter and a receiver, and the beam width measurement system was contrived. Subsequently, the proposed method and the system were verified by comparing the experimental results with the results of the conventional charge-coupled device technique.

• 한국광학회:학술대회논문집
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• 한국광학회 1988년도 광학 및 양자전자학 워크샵
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• pp.104-104
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• 1988

Single-mode 광섬유를 이용한 Sersor 및 그와 관련된 광섬유 device 의 작동원리 및 연구동향에 대하여 논의하였다. 논의된 광섬유 sersor 로는 intensity type sersor, fiber gyroscope, sensor array 등이 포함되어 있고, 관련 부품으로는 directional coupler, acousto-optic, fiber-optic amplifier 등이 설명되었다.

• 센서학회지
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• 제32권1호
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• pp.51-54
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• 2023

We investigated a humidity sensor based on a polyimide-coated side-polished optical fiber. The polyimide film absorbed moisture, causing the resonant wavelength of the sensor to shift to a longer wavelength owing to the changes in the optical properties of the film. The experimental results showed that the resonant wavelength of the device shifted by 17-18 nm when relative humidity changed from 30% to 90%.

• 한국광학회지
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• 제10권3호
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• pp.248-253
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• 1999

본 논문에서는 측면이 연마된 단일모드 광섬유와 폴리머 다중 평면도파로가 결합했을 때 발생하는 모드 결합현상을 이용한 능동형 광결합기를 연구하였다. 제안된 소자는 파장가변 광필터나 광변조기로 이용할 수 있을 뿐만 아니라, 광도파로 물질의 굴절률, 복굴절, 전기광학 계수, 열광학 계수 등을 측정하는 도구로 응용할 수 있다. BPM으로 최적화된 결합기를 설계하였고, 열광학 폴리머를 능동 평면 도파로층으로 이용하여 결합기를 제작하였다. 제작된 소자는 -0.5dB 이하 손실, 공진파장 -13dB 소멸비. 그리고 열광학 효과에 의해 -1.5nm/$^{\circ}C$ 정도의 파장 가변성을 보였다. 본 연구의 결과로 볼 때 열광학 능동형 광결합기는 광변조기, 파장가변 광필터, 광센서 등으로 이용될 가능성이 높다.

• Smart Structures and Systems
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• 제4권4호
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• pp.439-448
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• 2008

Optical fiber sensors are by now broadly accepted as an innovative and reliable device for structural health monitoring, to be used either embedded into or bonded on structures. The accuracy of the strain measurement achievable by optical fiber sensors is critically dependent on the characteristics of the bonding of the various interface layers involved in the sensor bonding/embedding (structure material and gluing agent, fiber coating and gluing agent, fiber coating and fiber core). In fact, the signal of the bonded/embedded optical fiber sensor must correspond to the strain experienced by the monitored structure, but the quality of each involved interface can affect the strain transfer. This paper faces the characterization, carried on by both mechanical tests and morphological analysis, of the strain transfer function resulting with epoxidic and vinylester gluing agent on polyimide and acrylate coated optical fibers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 B
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• pp.593-596
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• 1997

The main purpose of this paper is to develop sensing device of joint angle using loss of opfical fiber. The source of light to optical fiber is infrared rays diode, and receiver is a photo transistor. The bent angle of optical fiber is measured with rotary encoder, and The change of voltage due to the loss of light is measured with micro computer PIC16C74. The sensing device may be used to Functional Electrical stimulation(FES) System for Rehabilitation patient.