• 한국광학회:학술대회논문집
• /
• 한국광학회 2002년도 제13회 정기총회 및 2002년도 동계학술발표회
• /
• pp.270-271
• /
• 2002

• E2M - 전기 전자와 첨단 소재
• /
• 제9권3호
• /
• pp.246-250
• /
• 1996

In optical soliton transmission systems with nonlinear dispersive materials, which is utilized for ultra-long and high bit rate transmission, it is shown that the value of initial time difference between adjacent solitons is analyzed for optimum bit rate. The method is inducted by uncorrelation condition with minimum interaction forces in initial covariance coefficient between adjacent solitons. When the initial time difference is 6 times of soliton pulse width by the results, it is shown that the reliability is maintained with more than 90% within transmission length of soliton period. multiplied by 93.

• 대한화학회지
• /
• 제57권4호
• /
• pp.461-471
• /
• 2013

Optimized geometrical structure, atomic charges, molecular electrostatic potential, nonlinear optical (NLO) effects and thermodynamic properties of the title compound N-(2,5-methylphenyl)salicylaldimine (I) have been investigated by using ab initio quantum chemical computational studies. Calculated results showed that the enol form of (I) is more stable than keto form. The solvent effect was investigated for obtained molecular energies, hardneses and the atomic charge distributions of (I). Natural bond orbital and frontier molecular orbital analysis of the title compound were also performed. The total molecular dipole moment (${\mu}$), linear polarizability (${\alpha}$), and first-order hyperpolarizability (${\beta}$) were calculated by B3LYP method with 6-31G(d), 6-31+G(d,p), 6-31++G(d,p), 6-311+G(d) and 6-311++G(d,p) basis sets to investigate the NLO properties of the compound (I). The standard thermodynamic functions were obtained for the title compound with the temperature ranging from 200 to 450 K.

• Journal of Mechanical Science and Technology
• /
• 제15권3호
• /
• pp.309-319
• /
• 2001

This paper demonstrates the development of optical temperature sensor based on the etched silica-based planar waveguide Bragg grating. Topics include design and fabrication of the etched planar waveguide Bragg grating optical temperature sensor. The typical bandwidth and reflectivity of the surface etched grating has been ∼0.2nm and ∼9%, respectively, at a wavelength of ∼1552nm. The temperature-induced wavelength change is found to be slightly non-linear over ∼200$^{\circ}C$ temperature range. Typically, the temperature-induced fractional Bragg wavelength shift measured in this experiment is 0.0132nm/$^{\circ}C$ with linear curve fit. Theoretical models with nonlinear temperature effect for the grating response based on waveguide and plate deformation theories agree with experiments to within acceptable tolerance.

• 센서학회지
• /
• 제21권1호
• /
• pp.68-74
• /
• 2012

In this paper, Frequency Domain Mode Locked(FDML) wavelength swept laser with 55.027 kHz sweeping speed and 125 nm sweeping range has realized, and also a new method for recalibrating a nonlinear frequency sweeping of a swept laser has proposed. The Swept Source-Optical Coherence Tomography system using the proposed method has performed. For a mirror surface, the system showed the very clean 2-dimensional image and the advanced image speed of 7 frames per sec compared to the previous recalibration method.

• 한국광학회지
• /
• 제3권4호
• /
• pp.239-243
• /
• 1992

KDP 결정에서 2차 고조파가 발생될 때와 질소기체에서 CARS신호가 발생될 때 나타나는 간섭현상을 조사하였다. 비선형 신호들의 위상차이를 주기 위하여 광학유리를 이용하여 제작된 위상변이장치와 고압기체셀을 사용하였으며 각 매질에 대한 가간섭길이를 측정하였다. 특정한 스톡스광의 파장에서 CARS신호가 상쇄간섭을 일으키도록 위상변이장치의 두께를 조정한 후, 넓은 파장영역에서 상쇄간섭된 질소 CARS 스펙트럼을 얻었다. 위상변이장치의 두께를 바꾸면서 상쇄간섭정도의 변화를 관찰하였다.

• Bulletin of the Korean Chemical Society
• /
• 제16권2호
• /
• pp.126-129
• /
• 1995

Linear and nonlinear optical properties of CuCl nanocrystals in silica glass have been studied using low temperature absorption, degenerate four wave mixing (DFWM), and time-resolved photoluminescence spectroscopy. Assuming a spherical shape, effective radius of the CuCl quantum dots was estimated to be 2.5 nm, which is obtained from low temperature absorption data. The DFWM experiment was performed in 380-386 nm wavelength region, and the diffracted signal was measured as a function of wavelength with 1.0 nm interval. Time-resolved photoluminescence measurement was also carried out at 77 K to obtain the time response of CuCl nanocrystals. The experimental results on the large third order nonlinear optical of CuCl quantum dots are explained in terms of crystal size and oscillator strength of quantum spheres.

• Macromolecular Research
• /
• 제17권11호
• /
• pp.874-878
• /
• 2009

Photorefractive polymer composites were synthesized based on poly (N-vinylcazbazole) (PVK) doped with liquid nonlinear optical chromophores and a sensitizer $C_{60}$. PVK/liquid NLO chromophores/$C_{60}$ devices showed no signs of phase separation and did not require a plasticizer, such as ethylcarbazole. The composites showed 69% diffraction efficiency (C3) and a rapid response time of 46 ms (C1) in four-wave mixing experiments at a light intensity of $60\;mW/cm^2$ and a wavelength of 633 nm.

• 한국광학회지
• /
• 제1권1호
• /
• pp.40-45
• /
• 1990

반도체 실리콘은 띠간격 근처의 에너지를 갖는 광자를 흡수하여 생성된 전자-정공쌍에 의해 굴절률이 비선형적으로 변하며 이에 따라 입사한 광펄스를 변조시킨다. Finesse가 큰 실리콘 Fabry-Perot 간섭계를 형성할 때, 이를 투과하는 광펄스가 실리콘의 굴절률을 변화시켜 스스로 간섭계의 보강간섭조건을 만족시킴으로써 반치폭이 1/5까지 축약되는 현상을 관측하였다. 그리고 관측된 결과는 수치해석으로 구한 결과와 잘 일치하였다.

• 한국광학회:학술대회논문집
• /
• 한국광학회 2009년도 동계학술발표회 논문집
• /
• pp.149-150
• /
• 2009