• 한국광학회:학술대회논문집
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• 한국광학회 2006년도 하계학술발표회 논문집
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• pp.213-214
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• 2006

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.48-50
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• 2002

편광 유지 광섬유에 새겨진 장주기 격자의 파장에 따른 편광 의존 손실을 이용하여, 광섬유 브래그 격자가 사용된 광섬유 레이저에서 공동 내부 빛의 편광을 회전시킴에 따라, 발진 파장의 스위칭 및 이중 파장 발진이 가능함을 보였다.

• 한국광학회지
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• 제7권4호
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• pp.386-389
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• 1996

We report on comparative results obtained from harmonically mode-locked laser operations of ring-type and figure-of-eight(F8) type erbium-doped fiber lasers by using a directional-coupler type electro-optic modulator as an active mode-locker. The mode-locked and transform-limited pulses of 10.6 ps width were obtained at harmonics of the fundamental cavity frequency with the F8 type laser while mode-locked laser pulses greater than 15 ps were achieved with the ring type laser.

• Journal of the Optical Society of Korea
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• 제19권2호
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• pp.130-135
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• 2015

Based on the extended nonlinear Schr$\ddot{o}$dinger equation, the influences of the filter effect on pulse splitting in a passively mode-locked erbium-doped fiber laser with positive dispersion cavity are investigated theoretically. Numerical results show that, as the bandwidth of the spectral filter decreases, the nonlinear chirp appended to the pulse increases under the combined action of the filter effect of the super-Gaussian spectral filter and the self-phase modulation effect. On further decreasing the bandwidth, the wave breaking of the pulse takes place. In addition, by varying the pump power of the laser or the profile of the spectral filter, the influences of the filter effect on pulse splitting also change accordingly.

• 한국항해항만학회지
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• 제31권10호
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• pp.833-837
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• 2007

본 연구에서는 이득 평탄화된 어븀첨가 광섬유 증폭기를 제작하였다. 이득 평탄화 필터는 주기적으로 배열된 금속선을 이용하여 유도되는 장주기 광섬유 격자로 구현하였다. 980 nm 펌핑 레이저에 의해 증폭된 자발방출 출력 스펙트럼의 C-밴드 파장 영역에서 이득 리플을 제작된 필터를 적용하여 1 dB 이내로 억제하였다. 다중 채널을 동시에 증폭시킬 수 있는 성능은 페브리 페롯 레이저 다이오드를 이용하여 측정하였고 C-밴드에서 20 dB 이상 증폭시킬 수 있음을 보여주었다. 이 증폭기는 파장분할 다중화 방식의 장거리 광 전송에서 다중 채널을 동시에 증폭하는 효과적인 방법을 제공할 것이다.

• ETRI Journal
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• 제18권1호
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• pp.1-14
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• 1996

We have experimentally observed and theoretically analyzed the gain dependent optimum repetition rates of a hybrid-type active and passive mode locked laser pulses in an erbium-doped fiber laser of the figure-of-eight geometry by utilizing a nonlinear amplifier loop mirror (NALM) as a saturable absorber and a directional-coupler type electro-optic modulator as an active mode locker. Transform-limited mode-locked pulses of about 10 ps width were obtained at repetition rates which correspond to harmonics of the cavity fundamental frequency and depend on the optical amplifier gain in the NALM.

• Journal of the Optical Society of Korea
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• 제11권3호
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• pp.124-129
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• 2007

For the first time we compare two kinds of optical frequency combs, one of which is based on a Ti:sapphire femtosecond laser and the other is based on a mode-locked erbium-doped fiber laser. The comparison is performed by measuring an optical frequency standard with these two combs simultaneously. The two frequency measurements agree within 1.8 Hz ($3.8{\times}10^{-15}$) with the uncertainty of 17.2 Hz ($3.6{\times}10^{-14}$), from which it can be concluded that the Ti:sapphire-based frequency comb and the fiber-based frequency comb have no systematic discrepancy at this level of uncertainty.

• Journal of the Optical Society of Korea
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• 제11권1호
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• pp.44-48
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• 2007

A two-stage gain-clamped erbium doped fiber amplifier (GC-EDFA) using a pump laser diode and a 16 channel wavelength division multiplexing (WDM) with 0.8 nm spacing in C band of $1,545{\sim}1,560nm$ wavelength is experimentally demonstrated for a burst packet mode optical switching system.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 하계학술발표회
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• pp.142-143
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• 2000

파장분할 다중화 방식(WDM)이 광통신 시스템의 통신 속도를 획기적으로 향상시키는 방법으로 자리잡음에 따라 다파장 발생에 관한 많은 연구가 이어지고 있다. 지금까지의 연구 결과들은 크게 두가지로 나눌 수 있는 데, 넓은 대역의 이득 매질에서 다양한 방식의 파장선택 특성들을 이용하여 여러 개의 파장을 원하는 간격으로 발생시키는 방법$^{(1).(2)}$ 과 하나의 외부레이저 신호입사에 의한 유도산란을 통하여 일정한 파장간격을 가진 연속차수의 스토크스 신호를 발생시키는 방법$^{(3).(4).(5)}$ 이 있다. (중략)

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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• pp.96-97
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• 2000

Incoherent broadband optical sources have been applied in various areas such as a light source for optical device characterization, fiber-optic gyroscopes$^{(1)}$ , and spectrum sliced light source in wavelength division multiplexing (WDM) system$^{(2)}$ . To utilize the inherent low loss in silica optical fibers, various types of incoherent light sources are being developed. Among the light sources, the amplified spontaneous emission (ASE) from a rare earth doped fiber has benefits in temperature stability, high output power, low polarization dependence over semiconductor diodes$^{(3)}$ . Recently erbium doped fibers (EDF) have been intensively researched for ASE sources as well as optical amplifiers$^{(4)}$ . The spectrum of ASE from an EDF, however, is limited in the 1520~1560 nm range in conventional configurations. In this letter we described a new broadband ASE source which included both the conventional ASE band of Er$^{3+}$ ion, 1520nm~1560nm and ASE band from Tm$^{3+}$ ions that extends the bandwidth further. For the first time, to the best knowledge of authors, a fiber ASE source based on the energy transfer between Er$^{3+}$ and Tm$^{3+}$ ions in the range of 1460~1550 nm, has been demonstrated using a single 980nm pump laser diode. (omitted)omitted)