http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Z-scan 방법에 의한 비정질 As₂S₃ 박막의 비선형 굴절률 측정
김성규(Seong Gyu Kim),이영락(Yeung Lak Lee),곽종훈(Chong Hoon Kwak),최옥식(Ok Shik Choe),이윤우(Yun Woo Lee),송재봉(Jae Bong Song),서호형(Ho Hyung Suh),이일항(El-Hang Lee) 한국광학회 1998 한국광학회지 Vol.9 No.5
비선형 Kerr 매질을 통과하는 Gaussian 빔에 대해 aberration-free approximation과 Huygens-Fresnel 회절 이론을 적용하여 Z-scan 투과율에 대한 해석해를 유도하였다. 비정질 As₂S₃ 박막에 대해 Z-scan 실험을 수행하였으며 이론과 비교하여 잘 일치함을 알았다. 633㎚ 파장에서 측정된 비선형 굴절률 γ의 크기와 기호는 +8.65×10^(-6)㎠/W이며, 또한 먼 영역(far-field)에서 빔 세기분포를 측정하여 자기 집광(self-focusing) 효과를 가시적으로 확인하였다. We present a theoretical analysis of Gaussian beam propagation in nonlinear Kerr media by using aberration-free approximation and Huygens-Fresnel diffraction integral and obtain a simple analytic formular for Z-scan characteristics. Z-scan experiments are carried out on amorphous As₂S₃ thin film and compared with the theory developed, showing good agreement. The sign and the value of γ have been measured at 633 ㎚ to be +8.65×10^(-6)㎠/W. We also measured the far-field intensity profiles, which confirm again self-focusing effect.
단일모드 헬륨네온레이저를 사용한 초공진기(Super - Cavity)의 주파수 변조 분광연구
서호성(Ho Suhng Suh),윤태현(Tai Hyun Yoon),조재흥(Jae Heung Jo),정명세(Myung Sai Chung),류갑열(Gap Youl Lyu),김영덕(Yongduk Kim),최옥식(Ok Shik Choe) 한국광학회 1992 한국광학회지 Vol.3 No.1
주파수 변조 분광학(frequency modulation spectroscopy)을 이용하여 레이저 주파수의 안정화를 위한 초공진기의 주파수 변조 신호를 검출하였다. 단일모드 헬륨네온 레이저와 1.5 ㎒로 구동하는 전기광학 변조기를 이용하여 150 ㎑(3×10^(-10))의 고분해능을 갖는 초공진기의 주파수 변조 신호를 검출하였다. 또 위상민감검출기에 의한 기준신호의 위상이 각각 0° (동위상, in-phase), 90° (직각위상, quardrature phase)인 두개의 주파수 변조 신호 성분을 X축 및 Y축으로 하는 위상공간에서 주파수 변조 신호의 벡터궤적을 측정하고 주파수 변조 분광 신호를 해석하였다. 측정한 벡터궤적은 잠김증폭기(lock-in amplifier)의 기준 신호의 위상과 같은 각도로 회전함을 알았고 Bjorklund 등이 제시한 계수(modulus) 측정대신에 이 벡터 궤적을 이용할 경우 쉽게 주파수변조 분광 신호의 크기 뿐만아니라 기준 신호의 위상정보도 얻을 수 있음을 보였다. 측정된 주파수 변조 신호는 공진기 투과 중심 주파수 근방 ±1.5㎒ 이내에서 헬륨 네온 레이저 주파수가 존재할 때 이 주파수를 공진기의 투과 곡선의 중심에 안정화할 수 있는 주파수 분별곡선으로 사용할 수 있음을 보였다. Frequency modulation spectroscopy of the super-cavity, of which finesse is app. 40,000 has been demonstrated by using a sigle mode He-Ne laser. In-phase and quardrature components of frequency modulation signals (FM signal) were obtained by using the 1.5 ㎒-driven-electrooptic phase modulator. The vector locus of the FM signa in the phase space, which is consisted of in-phase and quardrature components of the FM signal, was observed and analyzed for the dependence of FM signal upon the phase of the reference signal of a phase-sensitive-detector. According to rotating the phase of the reference signal, the vector locus was observed to rotate with the same phase angle as the reference signal. The in-phase component of the FM signals will be used to stabilize the frequency of the He-Ne laser to the resonant frequency of the super-cavity.
崔玉植 嶺南大學校附設 基礎科學硏究所 1984 基礎科學硏究 Vol.4 No.-
Some spatial filterings are examined by means of Fourier Transform of lenses. The spectral distributions are numerically calculated via a personal computer which yields the graphical figures dotted by 200 points for each filtering. The effects of the spatial filterings are easilly interpreted, the rigor mathematical treatment, however, being remaining as untouchable, so far as discrete numerical data are concerned.
Kodak 649F Plates를 이용한 Dichromated Gelatin 홀로그래픽 감광재 처리 방법 연구
임용석,이영락,최옥식 嶺南大學校 基礎科學硏究所 1995 基礎科學硏究 Vol.15 No.-
Dichromated gelatin plays an important role to fabricate various kinds of holographic optical elements. In this study, we have investigated the processing method and the characteristics of dichromated gelatin recording materials by using Kodak 649F plates. The processing methods for obtaining high diffraction efficiencies and environmental stability which are necessary for the fabrication of the holographic optical elements are presented. Exposure characteristics, spectral and angular sensitivity, and the degradation of the diffraction efficiency versus time are measured. The maximum diffraction efficiency of the obtained holographic grating is about 90%.
全炳基,崔玉植 嶺南大學校附設 基礎科學硏究所 1981 基礎科學硏究 Vol.1 No.-
This paper show that the nucleon form factor can be obtained from dispersion relation and the calculation of absorption part and the obtained form factor formula fits to the recent experimental results.
홀로그래피 방식으로 발생된 위상공액파를 이용한 정밀 정렬
崔玉植 嶺南大學校 基礎科學硏究所 1993 基礎科學硏究 Vol.13 No.-
A precise alignment signal for a stepper equipment by means of TTL(through-the-lens) alignment has been chased using holographical phase conjugate waves as an alignment beam. The size of the alignment beam on the wafer was 4 ×60㎛, , and the alignment mark was the reflection type grating with the photoresist coated, 4 ×4㎛ squares with 8㎛ in pitch. The hologram generating the phase conjugate waves has been prepared on Agfa 870-E plate film with He-Ne laser(632.8nm, 5mW) in the amplitude type. The alignment beam has passed through the projection lens to form a line shaped illumination area on the wafer which then scanned the aligenment mark on the wafer. The diffracted beams by the alignment mark then passed back through the projection lens and were detected as the alignment signal at the detector. We were also able to obtain the alignment signals for the Al layer and for the bare layered photoresist wafers.
Dye Sensitized Dichromated Gelatin 박막의 홀로그램
임용석,최옥식,곽종훈 嶺南大學校 基礎科學硏究所 1997 基礎科學硏究 Vol.17 No.-
Dichromated gelatin (DCG) film is one of the best holographic recording materials because of its large refractive index changes, high resolution and high sensitivity to blue-green wavelength of light. The environmental stability of DCG film remains as a problem preventing their practical uses. Furthermore, DCG itself is insensitive to light of wavelength region by adding suitable dyes such as methylene blue (MB). However, the absorption of the material inevitably increases as adding MB dye into DCG, which results in attenuated gratings. In this work, we investigate the spectral sensitivity of MB-DCG film and the dependence of diffraction efficiency (DE) on the concentrations of MB for optimum hologram recordings. The experiment results are analysed based on the coupled wave diffraction theory for nonuniform gratings.
Choe,Ok-Shik,Choi,Sung-Chun 嶺南大學校附設 基礎科學硏究所 1986 基礎科學硏究 Vol.6 No.-
The variations of the actions under consideration were explicitly calculated under spatial translation, rotation, and time tranilation, and formal time variation calculus was made. In addition the variation of a reltivistic scalar field under translation was calculated in the same way.
Functional Differentiation for Quantum Electrodynamics
Choe,Ok-Shik,Choi,Sung-chun 嶺南大學校附設 基礎科學硏究所 1985 基礎科學硏究 Vol.5 No.-
Scattering amplitudes were expressed in terms of lengthy functional differentiation with respect to functions of sources. And functional differential equations were made by using the quantum electrodynamics Lagrangian in Coulomb Gauge.