• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.504-508
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• 2000

본 연구는 WDM(wavelength-division-multiplexed) 전송 시스템에서 안정된 파장의 광 송신기를 설계하고 구현하기 위한 것이다. 기본적으로 광 출력의 안정성을 위하여 10uA 미만의 안정성을 갖는 정전류 회로를 설계하려 했으며, 출력되는 광의 파장은 Wavelength Locker를 이용 에러신호를 검출하고, 이 신호로 레이저 다이오드 모듈 내부의 온도를 제어하여 파장을 조절하였다. 최종적으로 이들은 A/D, D/A 컨버터와 $\mu$-Processor로 구성된 마이컴 회로를 통해서 제어되도륵 하였다. 또한 마이컴 회로는 송신기가 WDM 전송 시스템에 장착되었을 때의 시스템과의 인터페이스를 위한 신호들을 출력할 수 있도록 하였다.

• 한국연소학회지
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• 제1권1호
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• pp.57-64
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• 1996

The atomizing characteristics in a spray injected from a twin fluid atomization nozzle have been investigated. The Sauter mean diameters as mean diameter are compared with wavelength calculated from the instability theory. The Sauter mean diameter are measured by the Fraunhofer diffraction theory using the Malvern particle sizer. The wavelength is calculated using the mean relative velocity instead of the exit relative velocity of nozzle. Also shadowgraphy technique is used to visualize atomization phenomena. This paper gives a possibility that the mean diameter can be predicted with the wavelength obtained by the simple instability theory.

• Journal of the Optical Society of Korea
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• 제16권1호
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• pp.17-21
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• 2012

A surface-normal input/output volume holographic grating coupler (VHGC) operating at 1550nm wavelength region by using a $10{\mu}m$-thick DuPont photopolymer film is designed and fabricated. The angular and wavelength responses of the input/output VHGC are investigated in order to validate applicability of this device in integrated optics and optical communications. The effect of incident-beam position on the output reflectance to determine optimum condition for input coupling is also presented. The fabricated input/output VHGC exhibited an angular selectivity of ${\sim}0.027^{\circ}$, a wavelength selectivity of ~0.8 nm, and an output peak reflectance of 34.13%.

• 전자공학회논문지D
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• 제35D권5호
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• pp.93-99
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• 1998

The chirping characteristics of InGaAsP electroabsorption modulatiors have been analyzed. The effective .alpha. parameters for large signal modulation were estimated by comparing the pulse shape after fiber transmission with constant chirping assumption.We investigated the structure and the operating condition of the modulator to improve the chirping characteristics. The .alpha. parameters were calculated as the function of wavelength detuning and the bias voltage. To minimize the chirping performance, high bias voltage and a small wavelength detuning and the bias voltage. To minimize the chirping performance, high bias voltage and a small wavelength detuning were preferred. An negative .alpha. value is achieved at the wavelength detuning below 30meV with a proper bias voltage so that pulse compression effect was expected.

• 대한전자공학회논문지SD
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• 제42권7호
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• pp.13-20
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• 2005

여러 개의 광섬유격자를 가변하여 파장변환과 스위칭이 가능한 다파장 EDF 링레이저를 제안하였다. 광섬유격자에 인가되는 압력을 변화시킴으로써 EDF 링레이저의 출력파장과 파장간격을 연속적으로 변환시킬 수 있었으며, 편광조절기를 조절하여 EDF 링레이저의 출력파장을 두 파장, 세 파장 또는 네 파장으로 스위칭 할 수 있었다.

• 전자공학회논문지D
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• 제34D권11호
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• pp.70-75
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• 1997

a wavelength division multiplexer based on a polymeric arrayed-waveguide grating has been designed and fabricated. A 4-channel multiplexer with a spacing of 3.2 nm is designe dby using te 2-dimensional beam propagation method. A UV-curable epoxy, NOA73, is used for the core layer, and a passive polymer, PMMA, for the cladding layer. The polymer waveguides are fabricated by the reactive ion etching method and their optical properties are characterized. The fabricted device has a center wavelength of 1548.3 nm, and the wavelength spacing between the channels is 3.2nm. The measured crosstalk is better than -18dB.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.938-941
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• 2003

As the application area of range finder initially developed for military purpose has been extended, the necessity of precision measurement for long distance and its miniaturization is being presented. Recently, LRF(Laser Range Finder) is widely used because it shows more accurate results of range finding. However, most of LRFs use laser source which have wavelength ranges harmful to the human eyes. In this study, we developed the LRF using OPO(Optical Parametric Oscillator) which can stretch laser wavelength to safe region and realized more compact one using solid state laser

• 전자공학회논문지D
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• 제34D권12호
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• pp.83-88
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• 1997

We present a fiber laser sensor that uses a fiber grating as a strain sensor head and an end-reflector of the laser cavity. A passive wavelength. The long-period grating band-rejection filter showed a wide usable filter wavelength range of about 25 nm, and the intensity of transmitted light increased by 16% for 1nm sensor wavelength shift in trhe measurement range.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.130-133
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• 2012

The Korea Institute of Energy Research(KIER) has began collecting solar radiation components data since January, 1988, and solar radiation classified wavelength data since November, 2008. KIER's solar radiation components and classified wavelength data will be extensively used by concentrating solar energy system users or designers as well as by research institutes.

• 한국광학회지
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• 제28권2호
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• pp.68-74
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• 2017

특정한 파장대역에서 파장변화에 따른 굴절능의 변화를 1차, 2차 미분까지 보정하여 기준파장과 그 인근 파장 대역에서 굴절능의 변화가 매우 적도록 안정화된 광학계를 설계하는 방법에 대하여 연구하고, 이를 적용하여 회절한계의 시준렌즈를 설계하였다. 설계된 광학계는 파장 변화에 대하여 매우 안정하였고, 파장 360~410 nm 대역에서 유효초점거리의 변화가 0.002% 이내로 매우 적었다.