• Annual Conference of KIPS
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• 2023.11a
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• pp.1131-1132
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• 2023

본 연구에서는 아두이노를 기반으로 하는 스마트 조도 반응 시스템을 구현한다. 조도센서를 활용해 주변 광량을 실시간으로 감지하고, 이를 기반으로 모터를 제어하여 편광 필터의 위치를 조절한다. 이 시스템은 강한 햇빛 조건에서 차선 인식의 명확성을 높이는 데 기여할 수 있을 것으로 생각된다. 현업에서 해당 기술을 사용하기 위해서는 추가적인 작업이 요구될 수 있지만, 본 연구는 새로운 아이디어의 탐색과 하드웨어의 구체적인 구현 방안을 제시함으로써 이후의 연구 방향성을 제안한다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.1
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• pp.47-57
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• 2002

In this paper, a wavelength converter for RZ data which can controls XPM in SOA by using polarization controller within optical fiber loop mirror is proposed and demonstrated. The proposed structure needs only one polarization dependent SOA for implementation compared to previous XPM ones and makes the cost down. And it provides wavelength converted signals with non-inverted and inverted pattern into outputs respectively.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.10
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• pp.7-13
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• 2009

By incorporating a polarization beam splitter and fiber coupler, we propose a fiber-optic multiwavelength-switchable interleaving filter that can function as a polarizaiton-independent transmission or reflection-type one. The proposed filter consists of a polarizaiton beam splitter and a Sagnac birefringence loop that is composed of a 50:50 coupler, polarizaiton-maintaining fibers, and two quarter-wave plates. In the proposed filter, a transmission-type filter with a channel isolation > 18[dB] or a reflection-type one with a channel isolation ~3[dB], whose channel spacing and switching displacement were 0.8 and 0.4[nm] in common, respectively, could be obtained. Channel interleaving operation could be performed by the proper control of waveplates within the Sagnac birefringence loop.

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.322-323
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• 2005

• Proceedings of the Optical Society of Korea Conference
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• 2004.02a
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• pp.260-261
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• 2004

• Korean Journal of Optics and Photonics
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• v.25 no.3
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• pp.131-136
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• 2014

In this paper we have implemented a temperature-insensitive polarimetric fiber strain sensor based on a Sagnac birefringence interferometer composed of a short polarization-maintaining photonic crystal fiber (PM-PCF), a 3-dB fiber coupler, and polarization controllers. The PM-PCF used as a sensor head was 2 cm long, which is the shortest length for a sensing element compared to other polarimetric fiber strain sensors using a PM-PCF. The proposed sensor showed a strain sensitivity of ${\sim}0.87pm/{\mu}{\varepsilon}$ with a strain measurement range from 0 to $8m{\varepsilon}$. The temperature sensitivity was also investigated and measured as approximately $-12pm/^{\circ}C$, when ambient temperature changed from 30 to $100^{\circ}C$. This temperature sensitivity is about 82 times smaller than that of conventional polarization-maintaining fiber (approximately $-990pm/^{\circ}C$). In particular, from a practical perspective we have experimentally and theoretically confirmed that the wavelength selected for the indicator dip location does not make a significant difference in the strain sensitivity.

• Korean Journal of Optics and Photonics
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• v.9 no.4
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• pp.270-273
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• 1998

We have demonstrated the wavelength tunable ultrashort pulse fiber ring laser proposed the novel method for measuring the cavity loss from relaxation oscillation frequency and the pump power. To suppress the polarization instability the laser cavity is configured with polarization maintaining fibers and to control the center wavelength a 2.4 nm bandwidth tunable wavelength filter was inserted in the cavity. The laser has 8 picosecond pulse width, 10 GHz repetition rate and 1.2 mW average power in 1530-1560 nm operation range.

• Journal of the Korean Magnetics Society
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• v.26 no.5
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• pp.149-153
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• 2016

In Fe/Gd multilayers, patterning effect on the interlayer coupling was studied by comparing patterned and unpatterned samples that were cut from a multilayer film. A comparative study of the two samples via temperature dependent Gd-specific magnetization vector using X-ray magnetic circular dichroism (XMCD) shows that the temperature dependence of the Gd magnetization vector can be modified in the patterned sample due to a competition between the patterning and antiferromagnetic interlayer coupling effects.

• Korean Journal of Optics and Photonics
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• v.26 no.6
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• pp.306-311
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• 2015

We report the characteristics of a single-wavelength-tunable fiber laser using a polymer waveguide Bragg grating (PWBG) wavelength filter. The output of the laser depends on environmental conditions, such as temperature and polarization states in the laser cavity. Wavelength tuning can be achieved, about 16.29 nm from 1548.24 nm to 1531.95 nm, according to the electric power applied to the PWBG wavelength filter. The achieved efficiency slope is about -0.16 nm/mW. A side-mode suppression ratio (SMSR) of more than 35 dB can be obtained by adjusting the polarization state in the laser cavity. A stable wavelength-tunable fiber laser can be achieved using the PWBG wavelength filter with a TEC module and a polarization-maintaining fiber.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.4
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• pp.381-389
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• 2005

To Analysis of Correlation of Visual Function Findings, by assessing convergence and accommodation, 92 selected objects without any ocular diseases by apperatuses of visual chart(Shinnippon CT30) and phoropter(Shinnippon VT10) at a shan distance(40 cm) were tested upon MEM retinoscopy(Welch Allyn, USA), BELL retinoscopy(Welch Allyn, USA), binocular accommodative facility (${\pm}2.00$ D nipper, Bernell Co., USA), vergence facility(prism nipper, Bernell Co., USA). The results showed as follows. MEM retinoscopy(accommodative lag) showed the same result of a right eye and left eye. Bell retinoscopy(accommodative lag) showed higher correlations between right and left eye than MEM. The lower accommodative lag meant the higher accommodative facility. The binocular accommodative facility(polaroid) was higher than binocular accommodative facility(red-green). Correlations of accommodative facility between right and left eye were higher, and as the higher monocular accommodative facility also meant the higher binocular accommodative facility, monocular and binocular accommodative facilities were relative to vergence facility, These findings can be used as a clinical guide by curing patients' visual function.