• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.326-327
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• 2003

제작한 광소자를 상용화하기 위해서는 광섬유와 연결하는 것이 필수적이다. 광섬유와 광소자를 결합하고 모듈화하는 일련의 과정, 줄여서 광패키징은 물리, 재료, 전자 및 기계에 관한 전체적인 이해를 요구하고 많은 경우 아직 한번도 다뤄본 적이 없는 문제를 해결해야 하는 경우도 발생하고, 경우에 따라 매우 엄밀한 조건을 충족시켜야 한다. 이러한 광소자 패키징은 광소자를 제작하는 것만큼 힘들고 정교한 공정을 요구해 광모듈의 가격에 큰 비중을 차지하고 있다. (중략)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1996.04a
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• pp.21-30
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• 1996

• Journal of the Institute of Convergence Signal Processing
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• v.9 no.3
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• pp.179-187
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• 2008

In this paper, we carried out the performance evaluation of depolarized fiber optic gyroscope(D-FOG) that was designed and fabricated with the low-cost optical communication single mode fiber and depolarizer. In order to reduce the phase error of D-FOG, the circuit of stabilized current and temperature of the light source was made and the performance was analyzed. The current and the temperature stability of the fabricated stabilization circuit were less than $200{\mu}A$ and $0.0098^{\circ}C$, respectively. Also, the D-FOG's experimental result showed that the value of the dynamic range of rotated rate, the scale factor error with a good linearity, and the zero bias drift were ${\pm}50^{\circ}/s$, 2.8881%, and $19.49^{\circ}/h$, respectively. The results indicated that a low-cost FOG was able to fabricate which was more cost effective than conventional FOG with a high-cost high-birefringent polarization maintaining fiber.

• Korean Journal of Optics and Photonics
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• v.8 no.4
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• pp.320-326
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• 1997

Broadband sources for fiber-optic gyroscope were constructed using erbium-doped fibers. Output power, linewidth, and mean wavelength were compared between four different source configurations. Among them, double pass configuration exhibited the highest output power, as high as 5.5 mW with 25 mW pumping at 1.48 ${\mu}{\textrm}{m}$ wavelength. It also showed nearly zero sensitivity of mean wavelength for the variation of pump power when a sufficient pumping was provided. Amplifier/Source configuration resulted in the highest detected power(power received by the gyro detector) that is more than 100 times larger than those of the other configurations, though it was the lowest of source output power. As the feedback level increased, the source power decreased while the linewidth increased, and mean wavelength varied significantly which would affect the scale factor of the gyroscope.

• Korean Journal of Optics and Photonics
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• v.14 no.6
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• pp.588-593
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• 2003

A signal processor for interferometeric fiber optic sensors, which measure dynamic quantities of frequency up to 1 KHz with high sensitivity, is developed. It is a high-speed version of the all-digital phase tracking (ADPT) processor that was used to measure static or slowly-varying quantities. The processor was applied to a fiber optic Mach-Zehnder interferometer to evaluate the performance. The measured total harmonic distortion was near to -50 ㏈, which is the theoretical limit or the ADPT signal processing.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.1
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• pp.83-89
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• 2004

• Journal of the Korean Institute of Navigation
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• v.19 no.1
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• pp.71-83
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• 1995

Various types of optical gyroscopes have been proposed and researched to the present in the world. This paper provides an overview of the types of optical gyroscopes, and also introduces technical principles, characteristics, advantages and disadvantages for each type. Moreover, the critical problems in a design have been discussed.

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.215-216
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• 2007

Isolator가 삽입된 Erbium 첨가 광섬유광원을 제작하였고 그 특성을 측정하였다. Isolator 삽입 유무에 따른 광섬유광원의 전 온도구간($-32^{\sim}75^{\circ}C$)에서의 중심파장 안정도는 수 ppm으로 큰 차이를 보이지 않았고, 귀환광 변화($-22^{\sim}-20dB$)에 따른 중심파장 안정도에서는 isolator 삽입이후에 1.6ppm으로 귀환광 변화에 매우 둔감한 결과를 얻었다.

• Korean Journal of Optics and Photonics
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• v.14 no.4
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• pp.460-465
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• 2003

Characteristics of 0.98 $\mu$m-pumped erbium-doped fiber (EDF) sources with double-pass forward (DPF) configuration are analyzed by numerical calculation. Various source characteristics such as output power, spectral width and mean-wavelength stability are investigated with the variation of EDF length, pump power and pump wavelength. Some of the numerical results are compared with experimental ones for verification. The results show that the characteristics of sources with DPF configuration can change considerably with the EDF length. It is also found that an optimum design can exist for stable mean-wavelength against fluctuations of pump power and pump wavelength.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.6
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• pp.1356-1363
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• 2005

In the gyrocompass system, the use of the fiber optic gyroscope(FOG) makes this traditional system considerably attractive because it has strong points in terms of weight, power, warming-up time, and cost. In this paper, a novel digital north-finding method based upon an FOG, which can be applied to the gyrocompass system, is proposed. The analytical model for the earth signal of the FOG is described, and the earth signals passed through lock-in amplifiers are modeled. Additionally, a north-finding algorithm using two lock-in amplifier outputs is developed, and the proposed method is organized by the developed algorithm. Simulation results are included to verify the performance of the proposed method.