• Title/Summary/Keyword: Glass Optical Fiber

Search Result 133, Processing Time 0.031 seconds

$^4I_{13/2}longrightarrow^4I_{15/2}$ Radiative Transitions of $Er^{3+}$ in $CaO-Al_2O_3$ Glasses ($CaO-Al_2O_3$계 유리에 함유된 $Er^{3+}$ 이온의 $^4I_{13/2}longrightarrow^4I_{15/2}$ 복사 천이 특성)

  • 원종원;박용완
    • Journal of the Korean Ceramic Society
    • /
    • v.31 no.8
    • /
    • pp.861-868
    • /
    • 1994
  • CaO-Al2O3 glass is a good candidate as optical fiber amplifier and laser. In this study, optical properties for 4I13/2longrightarrow4I15/2 transition of Er3+ ions doped in CaO-Al2O3 glasses were investigated. Optical absorptions, radiative transition probabilities and lifetimes for 4I13/2 level were evaluated by using Judd-Ofelt theory. Also, induced- emmision cross-sections of 4I13/2longrightarrow4I15/2 transition were calculated. Radiative transition probability and lifetime of 4I13/2 level were 144.6s-1, 690$mutextrm{s}$ respectively for 60CaO.40Al2O3 glass(FS0) and 152.6s-1, 660 $mutextrm{s}$ for 54 CaO.36Al2O3.10SiO2 glass (FS10). Each induced-emission cross sections for FS0 and FS10 was 0.749$\times$10-20 $\textrm{cm}^2$, 0.892$\times$10-20 $\textrm{cm}^2$. Obtained values were comparable with those of ZBLA glass studied as optical fiber amplifier and laser material.

  • PDF

Energy Transfer From Yb to Tm in Yb/Tm-doped Optical Fiber Amplifier

  • Watekar, Pramod R.;Ju, Seong-Min;Lin, Aoxiang;Han, Won-Taek
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2006.07a
    • /
    • pp.9-10
    • /
    • 2006
  • We report the realization of the Yb/Tm co-doped silica glass optical fiber amplifier operating at 1470 nm upon 980 nm pumping. The energy transfer coefficient from Yb to Tm was estimated using the threshold condition of the optical amplifier.

  • PDF

A study on the orthogonal cutting characteristics of glass fiber reinforced plastics (복합재료의 직교 절삭가공 특성에 관한 연구)

  • 송화용;정용운;김준현;김주현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 2001.10a
    • /
    • pp.155-160
    • /
    • 2001
  • In the use of glass fiber reinforced plastics(GFRP) it is often necessary to cut the components, but the cutting of GFRP is often made difficult by the delamination of the compositions and short tool life. Experimental investigation was conducted to evaluate the chip formation of the glass fiber reinforced plastics during orthogonal cutting. The chip formation process, cutting force, and thrust force were studied. The chip formation processes were studied through the use of quick-stop device. Chip-tool contact areas were obtained with the use of the quick-stop device, and observed using optical microscopy after polishing. Cutting force and thrust force were measured through the use of the tool dynamometer.

  • PDF

Polarization Insensitive Fiber-Optic Refractometer based on a Side-polished Fiber Coupler with a Thick Glass Waveguide

  • Sohn, Kyung-Rak;Song, Jae-Won;Kim, Hyung-Pyo
    • Journal of the Optical Society of Korea
    • /
    • v.6 no.3
    • /
    • pp.117-120
    • /
    • 2002
  • Side-polished single-mode fiber covered with a thick planar-glass-waveguide is studied as a polarization-insensitive fiber-optic refractometer The properties of the device are very sensitive to the index variation of an upper cladding on top of the overlay waveguide. We investigate the spectral response, the polarization properties, and the relationship between the shift in coupling wavelength and the index variation of an upper cladding layer Index resolutions of the order of 10-4 have been achieved.

Current-induced Phase Demodulation Using a PWM Sampling for a Fiber-optic CT

  • Park, Hyoung-Jun;Lee, June-Ho;Kim, Hyun-Jin;Song, Min-Ho
    • Journal of the Optical Society of Korea
    • /
    • v.14 no.3
    • /
    • pp.240-244
    • /
    • 2010
  • In this work, we used PWM sampling for demodulation of a fiber-optic interferometric current transformer. The interference signal from a fiber-optic CT is sampled with PWM triggers that produce a 90-degree phase difference between two consecutively sampled signals. The current-induced phase is extracted by applying an arctangent demodulation and a phase unwrapping algorithm to the sampled signals. From experiments using the proposed demodulation, we obtained phase measurement accuracy and a linearity error, in AC current measurements, of ~2.35 mrad and 0.18%, respectively. The accuracy of the proposed method was compared with that of a lock-in amplifier demodulation, which showed only 0.36% difference. To compare the birefringence effects of different fiber-optic sensor coils, a flint glass fiber and a standard single-mode fiber were used under the same conditions. The flint glass fiber coil with a Faraday rotator mirror showed the best performance. Because of the simple hardware structure and signal processing, the proposed demodulation would be suitable for low-cost over-current monitoring in high voltage power systems.

Computer Simulation Analysis on 2nd Order Optical Nonlinearity in Poled Silica Glass (Poling된 실리카 유리의 2차 비선형 광특성에 대한 전산모사 해석)

  • 이승규;유웅현;신동욱;정용재
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2001.02a
    • /
    • pp.230-231
    • /
    • 2001
  • Silica glass is a core material for optical fiber in optical telecommunications, but its centrosymmetry eliminates the second order nonlinearity. But it is experimentally well known that the space charge polarization induces the Second Harmonic Generation (SHG) when a strong DC voltage is applied to silica glass for a long period time with metal blocking electrodes. In this research, a theoretical calculation of the nonlinear optical property caused by the space charge polarization is performed, and a model of a numerical analysis to predict the small change in nonlinear optical property as functions of time and space is provided.

  • PDF

Measurement of POF Refractive Index Profile by using Phase-Shifting Moire Deflectometry (위상천이 모아레 간섭방법을 이용한 POF의 굴절률 분포 측정)

  • 우세윤;이현호;박승한
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2003.07a
    • /
    • pp.274-275
    • /
    • 2003
  • 광통신 분야의 연구 중 근거리 광통신 분야에 적용하기 위한 Plastic Optical Fiber(POF)에 관한 연구와 개발이 활발히 이루어지고 있다. POF의 광전송 특성을 결정짓는 요소 중 가장 중요한 특성이 바로 굴절률 분포이다. 이에 따라 그동안 다양한 형태의 POF 굴절률 측정 방법이 연구되어 왔다. 기존 Glass Optical Fiber의 굴절률 분포 측정 방법 중 가장 일반적이고 효과적인 방법 중 하나는 coherent 빛의 간섭을 이용한 transverse interferograms을 분석하는 방법으로 Fizeau 간섭계와 같은 간섭계를 이용하여 위상변화를 측정하고 측정한 위상을 tomography적인 해석방법을 통해 굴절률 분포를 계산하는 방법이다. (중략)

  • PDF

Micro lens system design for the optical fiber communication (광통신 변조기용 미세광학소자의 설계)

  • 홍경희
    • Korean Journal of Optics and Photonics
    • /
    • v.3 no.4
    • /
    • pp.217-221
    • /
    • 1992
  • A micro lens system was designed for the modulator in optical fiber communication. One was the collimating lens which transferred the diffracted beam from optical fiber to the modulator. The other was the coupling lens which connected the modulated collimating beam to the optical fiber. The light source was He-Ne laser beam. The lens would be made of optical glass BK-7. We determined the tolerance of curvature radius, thickness and conic constant.

  • PDF

Dependence of the Transmission Characteristics of Photonic Crystal Fiber on the Macrobending Radius and the Mechanically Induced Microbending

  • Lee, Byeong-Ha;Moon, Dae-Seung;Eom, Joo-Beom;Kim, Jin-Chae;Kim, Hok-Young;Paek, Un-Chul
    • Journal of the Optical Society of Korea
    • /
    • v.7 no.2
    • /
    • pp.72-78
    • /
    • 2003
  • It is reported that the spectral loss of photonic crystal fiber (PCF) having a large hole-to-hole distance (~ 10 ${\mu}{\textrm}{m}$) is sensitive to micro- and macrobending when compared with the conventional single-mode fiber. In this paper, we will present the measurement result of the macro- and microbending characteristics of fabricated PCF with large hole-to-hole distance (> 10 ${\mu}{\textrm}{m}$) . For the macrobending experiment, the fiber was simply wound around a circular structure with variable diameter that could be reduced to a few centimeters. For the microbending case, regularly spaced silica rods were attached on a slide glass and pressed against the fiber by loading a stack of metal plates of known weight on the glass. The transmission loss spectrum shows a rather flat response to the to microbending, and this makes the PCF a good candidate for a wideband variable optical attenuator.

Study on the Superprecision Glass Molding of Aspherical Lens for Optical Communication Module (광통신용 비구면 렌즈 초정밀 성형 공정 연구)

  • Jang, Kyung-Su;Lee, Tae-Ho;Rho, Tae-Yung;Kim, Chang-Seok;Jeong, Myung-Yung
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.27 no.1
    • /
    • pp.18-24
    • /
    • 2010
  • Efforts to obtain more efficient coupling of light from a laser diode to a single mode fiber have continued for various applications such as links for optical fiber communication systems. In TO-can package, configuration of optimized aspherical lens is bi-aspheric and its diameter is 2.4mm. We designed and fabricated aspherical coupling lens by means of glass molding technique under consideration of glass shrinkage. By controlling the aspherical profile error and surface roughness which were below 90nm and 10nm, respectively, we obtained the low coupling loss, 5.40dB, which was able to use for coupling a single mode fiber to laser diode.