• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.3
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• pp.20-20
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• 2001

광섬유고리에 편광제어를 통해 여러 광경로들에 대해서 손실을 조정함으로써 손실이 작은 광경로에서 발진하게 함으로써 발진 파장을 가변시킬 수 있는 편광제어 파장가변 고리형 광섬유레이저를 구현하였다. 내부 공진편광기를 사용하여 1㎚의 종모드간격으로 발진을 일으킬 수 있었고 편광제어기 및 내부공진편광기를 조절해서 1540㎚에서 1560㎚의 범위에서 파장가변을 시킬 수 있었다. 또한 실험적으로 나타난 발진특성을 광경로와 복굴절손실의 개념을 사용하여 발진출력 특성을 분석함으로써 발진파장을 가변시키는 메카니즘을 추정해 보았다. 여기서 복굴절손실이 같은 광경로들의 종모드들 사이에 보강간섭이 일어나 발진파장을 변화시킬 수 있음을 알 수 있었다.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.155-161
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• 1990

A Continous wave tunable $CO_2$ laser which is the slow axial flow type was construccted for the optical pumping of methyl alcohol ($CH_3OH$) laser. The reflective grating of 100 grooveslmm and 10.6$\mu\textrm{m}$ blaze wavelength was used to select wavelength. We have investigated continous outpu: power characteristics, and then have compared tuned output power profile with the gain curve of $CO_2$ laser. The optimum condition for maxium power was found at the gas mixing ratio 1 : 3 : 10 for $CO_2: N_2$ and He. under this condition the flow rate, pressure of lasing gas and discharge current are 9.5 llmin. 14 torr, and 55 mA respectively. The maxium output power was 55 Wlm. Output power of single wavelength operation was measured on 60 individual rotation vibration transitions in the P and K branches of the 9.5$\mu\textrm{m}$ band and 10.4$\mu\textrm{m}$ band in $CO_2$. The output power profile obtained from each band is well consistent with the gain curve of $CO_2$ laser and maxium tuned output power was 20 watt.

• The Journal of Engineering Research
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• v.3 no.1
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• pp.171-180
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• 1998

The low cost fiber ring laser can be tuned by controlling polarization states within the loop. In this paper, we investigate its operating principle and verify the performance through an experiment. This ring laser consists of a polarization controller and an intracavity polarizer for the wavelength tuner and semiconductor optical amplifier for the gain medium. It is seen that the lasing wavelength may be tuned through the range of 1540~1560 nm as a polarization controller and a polarizer are adjusted.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.40-41
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• 2001

파장가변레이저에서 널리 사용되는 이득매질로서 색소를 고체 상태로 사용하는 경우에는 색소를 폴리머 혹은 Sol-gel 형태의 호스트 매질에 침착시켜 고체화한다. 이와 같은 고체 상태로 색소를 사용하면 액체 상태로 색소를 순환시켜 사용하는 것보다 편리한 이점이 있다. 순환식 색소 레이저의 경우에는 레이저 광학계 이외의 색소 순환장치들이 첨가됨에 따라서 레이저 장치의 크기가 비대해지는 점에 반하여, 고체 색소 레이저의 경우에는 고체 색소 쎌로 대체됨에 따라서 소형의 레이저 장치로서 구성된다. (중략)

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.7 s.337
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• pp.13-20
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• 2005

We propose an erbium-doped fiber ring laser whose multi-wavelength oscillation is tunable and switchable by tuning fiber bragg gratings. By applying axial pressure on the fiber bragg grating, the wavelength spacing of the proposed laser can be tuned continuously. And by adjusting a polarization controller(PC), the proposed laser can be switched among dual-, triple- and four-wavelength lasing operations.

• Korean Journal of Optics and Photonics
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• v.17 no.3
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• pp.273-277
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• 2006

In this paper, we constructed the Littman type and fixed Littrow type tunable external-cavity diode laser systems. The laser output, which is the 0th-order diffracted beam from the diffraction grating in an external cavity, was the single longitudinal mode. Its FWHM was measured as less than 9MHz. With the diode driving current of 140mA and operating temperature of $25^{\circ}C$, the coarse tuning range of 5.375nm was measured for the Littman type, and of 13.65nm was measured for the fixed Littrow type. A fine tuning experiment in which an external mirror was rotated by a PZT driven by a sawtooth wave was performed, and its tuning range of 0.042nm was measured for both types. The fixed Littrow type tunable external-cavity diode laser system was an improvement on the conventional Littrow type tunable laser system in which the output direction varies due to the grating embedded in the mirror plate.

• Korean Journal of Optics and Photonics
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• v.4 no.2
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• pp.181-187
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• 1993

Optogalvanic spectrum of Ne has been obtained in the visible wavelength region 550-600 nm by using pulsed tunable dye laser. The recorded laser wavelengths are calibrated on the basis of the accurately-known Ne atomic transition lines. The accuracy of the measured wavelength is ${\pm}$ 0.005 nm. We tabulated the wavelengths and the relative intensities of the OG signals which are useful to calibrate the dye laser using R-590, R-610 dyes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1534-1541
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• 2000

Wavelength tunable fiber ring laser can be tuned by causing a resonance on the optical path having the least loss which is controlled by a polarization adjustment. It is observed that lasing wavelengths having 1 nm FSR(Free Spectral Range) can be tuned over the range of 1540-1560 nm when a polarization controller and an intra-cavit polarizer with 1.5 mm air gap are adjusted. The characteristics of wavelength shift in the laser output are analyzed by introducing an optical path modeling and the concept of a birefringence loss.

• Korean Journal of Optics and Photonics
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• v.19 no.3
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• pp.219-223
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• 2008

To realize a widely tunable laser diode, a polymer coupled-ring reflector is hybrid- integrated with reflective semiconductor optical amplifier. Even though ring-ring and ring-bus coupling ratios are changed by fabrication errors in waveguide width and height, they remain very close to the single peak condition, ensuring high yield in fabrication. The tuning range is observed to be about 35 nm, maintaining the side mode suppression ratio of about 30 dB.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.3
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• pp.174-184
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• 2001

Wavelength tunable fiber ring laser can be tuned by causing a resonance on the optical path having the least loss which is controlled by a polarization adjustment. It is observed that lasing wavelengths having 1 nm FSR(Free Spectral Range) can be tuned over the range of 1540~1560 nm when a polarization controller and an intra-cavity polarizer are adjusted. The tuning mechanism can be expected by analyzing the characteristics of the laser output using an optical path model and the concept of a birefringence loss. It is found that the constructive interference between longitudinal modes of different optical paths may cause wavelength tuning in the fiber ring laser.