• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.9
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• pp.1-6
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• 2000

Utilizing impurity free vacancy diffusion (IFVD) method, area selective intermixing of InGaAs/InGaAsP multi-quantum well (MQW) structure was done. After this, wavelength division demultiplexing waveguide type photodetectoers was integrated and measured. It showed large blue shift in bandgap due to intermixing of MQW. Photodetectors are based on typical p-i-n structure and devices having large and small bandgap areas line up linearly. Width of waveguide and length of each photodetector are 20 and 250 ${\mu}m$, respectively, TE/TM polarized light from tunable laser was butt-coupled to the photodetector and spectral response was measured. Photodetectors can demultiplexing 1480 and 1550 nm wavelength.

• Polymer(Korea)
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• v.24 no.5
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• pp.713-720
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• 2000

A polymer/iodine complex film was prepared using syndiotactic poly(vinyl alcohol) (s-PVA) with number-average degree of polymerization of 900 and syndiotactic diad content of 63.1%. In comparison with atactic-PVA/iodine films, degree of polarization of the s-PVA/iodine film was improved up to over 99% although a lower transmittance was obtained. By soaking in iodine/potassium iodide aqueous solution of a lower iodine concentration and subsequent drawing by 4 times, s-PVA/iodine film of a higher transmittance and degree of polarization was produced. The degree of iodine desorption of the s-PVA/iodine film in water were very low. The crystallinity and the d-spacing and crystal size of (100) plane increased at the early stage of soaking time, however, remained constant or decreased slightly with increasing soaking time. In consequence, s-PVA/iodine complex formation took place mainly inside crystal region at the initial stage of soaking time, whereas it occurred outside crystal region or physical adsorption of iodine dominated after sufficient soaking.

• Korean Journal of Optics and Photonics
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• v.13 no.6
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• pp.467-472
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• 2002

In this paper, we propose a polarization-insensitive temperature sensor using a thermo-optic effect of the upper and (or) lower cladding of a planar waveguide in contact with a side-polished fiber. A microscope cover glass with thickness of a 170 ${\mu}{\textrm}{m}$ is adopted as an overlay waveguide because this waveguide opposes sudden temperature change and ensures polarization-insensitive responses. The measured polarization-dependence loss is less than 0.3 dB. The temperature can be detected as a result of the shift in coupling wavelength of the sensor. We investigate the shift in coupling wavelength as a function of the temperature variation with respect to the different thermo-optic coefficients of lower and upper claddings. We also show that the temperature sensitivity of the device can be easily controlled by the thermo-optic coefficients of lower and upper claddings of the overlay waveguide.

• Journal of the Korea Society of Computer and Information
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• v.24 no.11
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• pp.71-78
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• 2019

Most 3D displays that are currently in the market adopt the binocular disparity method creating a different image for the left and right eye for a 3 dimensional effect. However, commercialized 3D image output devices lack in performance making it uncomfortable for the viewer and restrict the viewer to certain positions. In this paper, we propose a single-cell polarized lens type stereoscopic system which has a smaller viewing angle and reduced crosstalk, with improved light penetration compared to existing double-cell structures; and analyzed the single-cell polarized lens type stereoscopic system properties, and conducted an effect analysis of performance improvement compared to the dual-cell type. Results showed that the single-cell type had a 25% improved performance, and the 3D crosstalk index which is an important index for quality characteristics of stereoscopic systems, increased over about 37%, compared to the dual-cell type.

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.56-57
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• 2005

• The Bulletin of The Korean Astronomical Society
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• v.32 no.1
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• pp.28.2-28.2
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• 2007

• 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

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.451-452
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• 2006

• Information and Communications Magazine
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• v.25 no.10
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• pp.58-65
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• 2008

본고에서 최근 초고속 광전송 시스템의 연구/개발 동향을 소개한다. 폭발적으로 증가하고 있는 통신 트래픽을 경제적으로 수용하기 위하여 초고속 광전송 시스템은 오류 정정 코드, 라만 광증폭기, 새로운 변조 방식, 전송 링크 분산 제어, 등화기, 편광 다중화 방식등의 새로운 기술들을 도입하여 용량 및 전송 거리를 증가시키고 있다.

• Proceedings of the Korean Society of Rheology Conference
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• 2006.06a
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• pp.67-70
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• 2006