• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.112-113
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• 2006

In this paper. we investigated a characteristic of holographic grating data erasure with non-polarized beam at amorphous chalcogenide As-Ge-Se-S thin film. A sample of holographic grating data was formed with DPSS laser for setup. Then, the erasure process was performed with He-Ne laser vertically at sample. As-Ge-Se-S(single layer). Ag/As-Ge-Se-S(double layer) and As-Ge-Se-S/Ag/As-Ge-Se-S(multi-layer) are manufactured to compare their characteristic of erasure.

• Journal of the Optical Society of Korea
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• 제20권1호
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• pp.70-77
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• 2016

This paper proposes an optical system for complex holographic display that enhances the quality of the reconstructed three-dimensional image. This work focuses on a new design for an optical system and the evaluation of the complex holographic display, using a single spatial light modulator (SLM) and a circular grating. The optical system is based on a 4-f system in which the imaginary and real information of the hologram is displayed on concentric rectangular areas of the SLM and circular grating. Thus, this method overcomes the lack of accuracy in the pixel positions between two window holograms in previous studies, and achieves a higher intensity of the real object points of the reconstructed hologram than the original phase-reconstructed hologram. The proposed method provides approximately 30% less NMRS (Normal Root Mean Square) error, compared to previous systems, which is verified by both simulation and optical experiment.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권9호
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• pp.423-428
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• 2006

We have been carried out the two-beam interference method to form the diffraction grating on chalcogenide $AS_{40}Se_{15}S_{35}Ge_{10}$ thin films for Holography Data Storage (HDS). In the present work, we have been formed holographic diffraction gratings using He-Ne laser (632.8nm) under different Polarization state combinations (intensity polarization holography, phase polarization holography). It was obtained the diffraction grating efficiency by 11st order intensity and investigated the formed grating structure using Atomic Force Microscopy (AFM). As the results, it is shown that the diffraction efficiency of (P: P) polarized recording was maximum 2.4% and we found that its value was rather higher than that of other-polarized recordings. From the results, it is confirmed that the efficient holographic grating formation on amorphous chalcogenide $AS_{40}Se_{15}S_{35}Ge_{10}$ films depend on both the spatial variation of intensity and the polarization state of the incident field pattern.

• ETRI Journal
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• 제41권1호
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• pp.42-51
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• 2019

The rainbow hologram provides views of reconstruction with rainbow color within a large viewing zone. In our recent paper, a Fourier rainbow holographic display using diffraction grating and a white-light LED source was introduced. In this technique, the rainbow effect is realized by the dispersion of white-light source on diffraction grating, while the slit is implemented numerically by reducing the demands of the space-bandwidth product of the display. This paper presents a novel analysis on the visual perception of the Fourier rainbow holographic display using Wigner distribution. The view-dependent appearance of the image, including multispectral field of view and viewing zone, is investigated considering the observer and the display parameters. The resolution of the holographic view is also investigated. For this, a new quantitative assessment for image blur is introduced using Wigner distribution analysis. The analysis is supported with numerical simulations and experimentally captured optical reconstructions for the holograms of the computer model and real object generated with different slit size, reconstruction distance, and different observation conditions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.89-92
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• 1998

Amorphous chalcogenide thin films, especially a-(Se, S) based films, exhibit a number of photoinduced phenomena not observed in other types of amorphous thin films. The polarization holographic grating has been formed in amorphous As-Ge-Se-S thin films using two linearly polarized He-Ne laser light. In addition, dffraction efficiency has been measured by the same laser of a relative lower intensity at the same time.

• Journal of the Optical Society of Korea
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• 제14권4호
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• pp.305-309
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• 2010

Photopolymer films containing fluorescent anthracene polymer, polymethyleneanthracene (PMAn), were prepared with different concentrations of PMAn for holographic recording useful for security documents. The fluorescent photopolymer film showed enhanced fluorescent intensity due to the micro-separation which arose from grating formation and diffusion during photopolymerization. Experimental values of diffraction efficiency were well matched to the simulated values for photopolymers having different PMAn concentrations. Holography patterning was carried out using the fluorescent photopolymer under a photo-mask. A grating was confirmed using microscope techniques in the recorded area under the pattern. Importantly the recorded area showed enhanced fluorescence compared to the unrecorded part, allowing fluorescence patterns at micro scale along with the submicron grating pattern. The fluorescence pattern recorded on the photopolymer film provides additional readability of holographic reading and thus is useful for secure recording and reading of information.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.107-107
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• 2010

In this study, we have investigated the holographic grating formation on Ag-doped amorphous chalcogenide AsGeSeS thin films with Ag thickness. Ag/AsGeSeS thin films with the incident laser beam wavelength for the improvement of the polarization diffraction grating efficiency. Holographic gratings have been formed using Diode Pumped Solid State laser (DPSS, 532.0nm) under [P:P] polarized the intensity polarization holography. The diffraction efficiency was obtained by +1st order intensity. The result is shown that the diffraction efficiency of Ag/AsGeSeS double layer thin film for the Ag thickness, the maximum grating diffraction efficiency using 60nm Ag layer is 0.96%.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.1042-1045
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• 2002

We have carried out two-beam interference experiments to form holographic gratings on amorphous $MgF_2$/As-Ge-Se-S multi-layer. In this study, holographic gratings have been formed using He-Ne laser(632.8nm). under different polarization combinations. The diffraction efficiency was obtained by +1st order intensity. The maximum diffraction efficiency of As-Ge-Se-S single layer and $MgF_2$/As-Ge-Se-S multi-layer were 0.8% and 1.4%

• 융합신호처리학회논문지
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• 제9권4호
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• pp.261-271
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• 2008

홀로그래픽 부피격자 커플러(VGC : volume grating coupler)는 높은 선택적 결합효율, 건식 제조공정, 콤팩트한 소자 제작이 가능하고 저렴하기 때문에 광연결 기술의 구현 및 응용에 매우 매력적인 소자로 간주되고 있다. 본 논문에서는 도파로형 광연결에 적용키 위한 $45^{\circ}$ 격자 경사각을 갖는 도파로 삽입형 입 출력 VGC를 DuPont사의 HRF600-20 홀로그래픽 포토폴리머를 이용하여 설계, 구현하기 위한 방법을 제안하였다. 그리고 제안한 VGC 소자의 유용성을 입증키 위해 동작파장이 각각 632.8nm 및 1550nm인 VGC를 제작하고 실험결과를 제시하였다. 실험결과 632.8nm 파장에서 동작하는 격자주기가 $0.5{\mu}m$인 단일 VGC의 경우 TE 편광에서 입력 결합효율은 86.6% 이상이고, 1550nm 파장에서 동작하는 격자주기가 $0.73068{\mu}m$인 $1\times2$ VGC의 입력 결합효율은 $\sim90.9%$의 특성을 나타내었다.

• 전자공학회논문지A
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• 제33A권6호
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• pp.108-113
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• 1996

Periodic gratings for 1.55$\mu$m distributed feedback laser diode (DFB LD) have been fabricated by a holographic interference exposure system using an etalon stabilized Ar ion laser. We obtain a good development condition at developer concentration of 65% and obtain etching rate of 1000$\AA$/min at 20.deg. C by the mixed solution HBr:HNO$_{3}$:H$_{2}$O(1:1:10 in volume ratio). We obtain good first order grating with period of 2400${\AA}[\pm}2{\AA}$ at etching time of 45 sec from grating period and diffraction efficiency measurement, and SEM observation of grating fabricated on InP substrate.