• Title/Summary/Keyword: 회절효율

Search Result 276, Processing Time 0.021 seconds

A study on the eliminating using non-Polarization beam on film of As-Ge-Se-S (As-Ge-Se-S 박막에서 비편광빔을 이용한 회절격자의 소거에 관한 연구)

  • Lee, Ki-Nam;Kim, Chang-Hyoung;Park, Jung-Il;Chung, Hong-Bay
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2005.07a
    • /
    • pp.514-515
    • /
    • 2005
  • 본 논문에서는 As-Ge-Se-S 박막에 (P:P) 편광빔을 이용하여 회절격자를 형성시키고 비편광 (Non-Polarization) 빔을 이용하여 생성된 격자를 소거시키고 그에 따른 회절효율을 조사 하였다. (P:P) 편광으로 기록된 회절 효율은 시간이 지나도 최대 회절효율의 변화가 없었으나 비편광 빔으로 기록된 회절효율은 시간이 지남에 따라 급격한 회절효율의 감소를 보인다. 따라서 (P:P) 편광으로 회절격자를 형성시키고 비편광빔으로 격자의 소거를 진행하여 약 83%의 회절격자의 소거가 이루어졌다.

  • PDF

Diffraction Efficiency Characteristics of Holographic Grating derived from Slavich PFG-01 by a Bleach Technique (표백방법에 따른 Slavich PFG-01 홀로그래피 회절격자의 회절효율 특성)

  • Lim, Chun-Woo;Sohn, Sang-Ho
    • Journal of Science Education
    • /
    • v.34 no.2
    • /
    • pp.203-210
    • /
    • 2010
  • The characteristics of diffraction gratings, fabricated using Slavich PFG-01 plates as a holographic recording material, were investigated using various bleach techniques. The changes in diffraction efficiencies, under given development conditions, resulting from the use of a new reversal bleach and a new fixation free rehalogenating bleach are investigated. From the experimental results, it was found that the diffraction efficiencies are influenced by the composition of the developer, the reversal bleach and the fixation free rehalogenating bleach. In this study, the highest values of the maximum diffraction efficiency was obtained when PFG-01 plates were developed in AAC developers contained with l-ascorbic acid 20 g/L and sodium carbonate 60 g/L, processed by a reversal bleach, as high as 89.0%. Moreover, the maximum diffraction efficiency of 82.1% was obtained when PFG-01 plates were processed by a fixation free rehalogenating bleach. In addition, higher diffraction efficiencies are yielded in the case of the revesal bleach than in the case of the fixation free rehalogenating bleach.

  • PDF

The changed diffraction efficiency depend on annealing of amorphous chalcogenide films (비정질 칼코게나이드 박막의 열처리에 따른 회절효율 변화)

  • Lee, Ki-Nam;Yeo, Cheol-Ho;Sin, Kyung;Chung, Hong-Bay
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2004.11a
    • /
    • pp.590-593
    • /
    • 2004
  • 본 논문에서는 $As_{40}Ge_{10}Se_{15}S_{35}$ (300nm)박막과 $As_{40}Ge_{10}Se_{15}S_{35}$ (300nm)/Ag(20nm)박막에 홀로그래피 격자를 형성시킨 후 Tg 온도$(240^{\circ}C)$를 기준으로 하여 유리질 천이온도(Tg) 온도 이하 $(190^{\circ}C)$와 이상$(270^{\circ}C)$에서 열처리 시킨 후의 회절효율 변화를 알아보았다. $As_{40}Ge_{10}Se_{15}S_{35}$ (300nm) 박막의 경우 $190^{\circ}C$ : 50%, $240^{\circ}C$ : 약80%, $270^{\circ}C$ : 약 98%의 회절효율 감소가 일어났으며 $As_{40}Ge_{10}Se_{15}S_{35}$(300nm)/Ag(20nm)박막에서는 Tg 온도 이하 즉 $190^{\circ}C$, $240^{\circ}C$ 에서는 회절효율의 변화가 없었으나 Tg온도 이상인 $270^{\circ}C$에서는 약 1.5배 증가한 회절효율을 나타내었다.

  • PDF

Fabrication of High Efficiency Silver Halide Holograms by Reversal Bleaching Process (반전표백 방법에 의한 고효율 은염건판 홀로그램 제작)

  • 백성훈;홍석경;김철중
    • Korean Journal of Optics and Photonics
    • /
    • v.2 no.2
    • /
    • pp.89-95
    • /
    • 1991
  • High diffraction efficiency holographic gratings in silver halide emulsion were fabricated by using reversal bleaching process. The diffraction efficiencies of gratings were improved greatly by applying rapid drying procedure with isopropyl alcohol after bleaching with optimized developers. The dependency of diffraction efficiencies on the different groups of developers, the concentration of bleaching solutions, and the drying methods are investigated experimentally and the results were analyzed theoretically. Same as usual reversal bleaching process, the fabricated gratings showed very low scttering compared to those made by conventional bleach process. The maximum diffraction efficiency was 88%.

  • PDF

Diffraction-efficiency Correction of Polarization-independent Multilayer Dielectric Gratings (무편광 유전체 다층박막 회절격자의 효율 보정)

  • Cho, Hyun-Ju;Kim, Gwan-Ha;Kim, Dong Hwan;Lee, Yong-Soo;Kim, Sang-In;Cho, Joonyoung;Kim, Hyun Tae
    • Korean Journal of Optics and Photonics
    • /
    • v.33 no.1
    • /
    • pp.22-27
    • /
    • 2022
  • We fabricate a polarization-independent dielectric multilayer thin-film diffraction grating for a spectral-beam-combining (SBC) system with a simple grating structure and low aspect ratio. Due to the refractive index and thickness error of the manufactured thin films, the diffraction efficiency of the fabricated diffraction grating was lower than that of the design. The causes of the errors were analyzed, and it was confirmed through simulation that diffraction efficiency could be compensated through an additional coating on the manufactured diffraction grating. As a result of sputtering an additional Ta2O5 layer on a fabricated diffraction grating, the diffraction efficiency was corrected and a maximum 91.7% of polarization-independent diffraction efficiency was obtained.

Analysis of Polarization Characteristics of Reflection Type Photopolymer for Stabilization (반사형 광 폴리머의 효율 안정을 위한 편광특성 분석)

  • Kim, Eun-Seok;Kim, Nam
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.37 no.7
    • /
    • pp.36-42
    • /
    • 2000
  • Some polarization characteristics of reflection type photopolymer are investigated. Photopolymer on a Mylar substrate alters an incoming linearly polarized laser beam to an elliptical polarization. Due to the rotation of the polarization, the recording gratings show different diffraction efficiencies. The rotation angle is of order of 10-50% for the tested samples. It is found that the polymer layer does not changes the polarization direction but the Mylar substrate alone distorts the incoming polarization to a comparable degree. As align the polarization states of photopolymers to be parallel with a laser using a He-Ne laser(633nm), which is not sensitive to that material, it was possible to make high diffraction efficiency gratings.

  • PDF

Design of High Efficiency Transmission Dielectric Grating for Chirped Pulse Amplification (CPA 시스템 구성을 위한 고효율 투과형 유전체 회절격자 설계)

  • Cho, Hyun-Ju;Jung, Jae-Woo;Lee, Sang-Hyun;Kim, Soojong;Lee, Jeongseop;Jin, Daehyun;Jung, Jiho;Son, Seonghyun
    • Korean Journal of Optics and Photonics
    • /
    • v.33 no.6
    • /
    • pp.260-266
    • /
    • 2022
  • A diffraction grating structure composed of two matching layers and two grating layers was formed, and a diffraction grating with high transmission diffraction efficiency in the -1st order was designed through an optimization technique. The designed diffraction grating had a transverse electric wave diffraction efficiency of 99.997% at the design center wavelength, and had a wavelength width of 80 nm and an incident angle width of 20.0° that maintained a diffraction efficiency of 95% or more. By performing the grating tolerance analysis, it was confirmed that the thickness tolerance for a diffraction efficiency of 95% or more was secured to at least 60 nm, and the diffraction efficiency could be maintained even in a trapezoidal shape with an internal angle of less than 10°.

Diffraction Efficiency and Analysis for Conditions of CGH (CGH 조건에 따른 회절효율 측정 및 분석)

  • Seo, Young-Ho;Lee, Yoon-Hyuck;Kim, Dong-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2018.05a
    • /
    • pp.435-436
    • /
    • 2018
  • In this paper, diffraction efficiency for computer-generated hologram (CGH) generated under various conditions was measured. This paper discusses the generation conditions that should be considered in hologram reconstruction. We compared each condition by measuring the intensity of the 1st order diffraction pattern of the fringe generated under the Fresnel condition for the phase and complex hologram.

  • PDF

Light-intensity Dependence of Diffraction Efficiency in - $Fe:LiNbO_3$ Crystals - (빔세기에 따른 $Fe:LiNbO_3$ 결정의 회절효율)

  • 정태혁
    • Korean Journal of Optics and Photonics
    • /
    • v.4 no.3
    • /
    • pp.323-329
    • /
    • 1993
  • In this paper, dependence of the diffraction efficiency upon incident light intensity is studied. The conductivity ratio, which is dependent upon the incident light intensity, changes the static electric field in a crystal. This change of the static electric field modulates the refractive index via linear electro-optic effect. And the change of the refractive index affects the diffraction efficiency. It is found that experimental results with $Fe:LiNbO_3$ crystals are in good agreement with the theory.

  • PDF

Simulation estimate of micro fresnel lens (Micro fresnel lens 시뮬레이션 평가)

  • Shin, S.Y.;Park, H.D.;Park, K.B.;Kim, K.N.;Lee, B.N.;Jeong, S.W.;Kim, I.H.;Moon, H.C.;Shin, S.M.
    • Proceedings of the KIEE Conference
    • /
    • 1999.11d
    • /
    • pp.1148-1150
    • /
    • 1999
  • Fresnel lens는 zone plate에 비해 공정은 쉬우나 회절 효율이 높은 것으로 알려져 있다. 본 논문에서는 micro fresnel lens를 설계하고 각각의 회절 효율 및 focal size를 계산하였으며. 비교적 공정이 용이한 계단 모양의 fresnel lens를 설계하여 회절 효율과 focal size를 계산하였다. 그리고, 광원의 파장과 초점거리에 따른 lens의 회절 효율을 비교하였으며, 계단의 수에 따른 회절 효율도 비교하였다.

  • PDF