• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 동계학술발표회 논문집
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• pp.199-200
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• 2008

In this paper, we researched optical characteristics of a holographic optical security system using a reflection recording material and optical random phase mask. The system have the property of optical security key with the phase mask. Also, a reflection recording geometry can reduced a size of the reconstruction system because a input beam to reconstruct a holographic image and a diffraction beam are the same side on the material.

• 한국광학회:학술대회논문집
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• 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.112-114
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• 1990

A method for fabrication of holographic optical elements (HOE) using dichromated gelatin (DGG) as a recording material is presented. we describe the holographic properties of the DGG and the processing techniques. Holographic characteristics of the DGG including exposure characteristics, diffraction efficiency and angular sensitivity are also discussed. The diffraction efficiency of the obtained holographic grating is about 84%.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.47-50
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• 1987

There are various holographic recording materials, such as Dichromated Gelatin, Silver Halide, Thermoplastic, Photoresist. In this paper especially, we used Photoresist to make the phase holographic grating. Deep-groove diffractive grating formed in relatively thin holographic recording material is to express high diffraction efficiency. Phase holographic grating recorded In photoresist can be used very practical because it has the high diffraction efficiency, and it is possible to make a replication easily. So, it has the merit in recording the optical holographic grating than any other materials.

• Transactions on Electrical and Electronic Materials
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• 제7권3호
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• pp.141-144
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• 2006

In the present work, we investigated the holographic grating erasing method by means of the optical method. It was formed the grating under the interference of holographic recording He-Ne laser beams on chalcogenide $As_{40}Ge_{10}Se_{15}S_{35}$ thin film with various film thickness and erased the holographic grating by non-polarized He-Ne laser beam. As the results, the recording grating erased the 80 % of formed grating by non-polarized He-Ne laser beam. It was confirmed that the erasing characteristics by non-polarized laser beam need to improve the focusing of beam and the control of beam intensity. And then it can be expected as the application possibility of rewritable holographic memory technology.

• Bulletin of the Korean Chemical Society
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• 제23권4호
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• pp.571-574
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• 2002

The photorefractive polymeric composite with good performance was prepared. The carbazole-substituted polysiloxane sensitized by 2,4,7-trinitro-9-fluorenone was used as a photoconducting medium and 1-[4-(2-nitrovinyl)phenyl]piperidine was added as an optically nonlinear chromophore. The photorefractive property of polymer was determined by diffraction efficiency using a 100 ㎛-thick film. The maximum diffraction efficiency ( ηmax) of 71% was obtained at the electric field of 70 V/ ㎛. The potential of the current polymer material as a holographic recording medium was evaluated by the demonstration of holographic recording and subsequent reading of optical image.

• 한국전기전자재료학회논문지
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• 제23권5호
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• pp.403-407
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• 2010

This paper shows that the diffraction efficiency is influenced by superadditivity for the combination of the different developing agent and concentrations in the reversal bleach applied to the Slavich PFG-01 plate to be used for recording transmission holograms. The four developers based on ascorbic acid in combination with metol, phenidone, hydroquinone respectively, were studied. In diffraction efficiency aspect, the superadditivity effect of mixture of two developing agents is lower than one developing agent developer, AAC in the reversal bleach.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.92-95
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• 2005

The silver photodoping effect in amorphous AsGeSeS chalcogenide thin films for holographic recording has been investigated using a HeNe laser ($\lambda$=632.8 nm). The chalcogenide films prepared in this work were thinner in comparison with the penetration depth of recording light ($d_p$=1.66 mm). The variation of the diffraction efficiency $(\eta)$ in amorphous chalcogende films exhibits a tendency, independently of the Ag photodoping. That is, n increases relatively rapidly at the beginning of the recording process, reaches the maximum $({\eta}_{max})$ and slowly decreases. In addition, the value of ${\eta}_{max}$ depends strongly on chalcogenide film thickness(d) and its peak among the films with d = 40, 80, 150, 300, and 633 nm is observed at d = 150 nm (approximately 1/2n), where n is refractive index of the chalcogenide (n=2.0). The ${\eta}$ is largely enhanced by Ag photodoping into the chalcogenides. In particular, the value of hmax in a bilayer of 10-nm-thick Ag/150-nm-thick AsGeSeS film is about 1.6%, which corresponds to ~20 times in comparison with that of the AsGeSeS film (without Ag).

• 정보저장시스템학회논문집
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• 제3권1호
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• pp.13-16
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• 2007

The purpose of this paper is real time tilt servo control of the holographic data storage system. Holographic data storage device is a next generation data storage device with high storage density, high transfer rate and short access time. This device is very sensitive to a disturbance due to the enormous storage density. As to the recording material changed disc type, the media continuously vibrates as the disc rotates. When disc rotates, deviation, eccentricity and unbalance disturbance are occurred. This disturbances cause disc tilt, finally reference beam does not illuminates to correct incidence angle. Therefore real time tilt servo control is essential. In this paper, the algorithm is proposed to make real time tilt detection in angle multiplexing of the holographic data storage system with an additional servo beam and the experiments are performed.

• 한국통신학회논문지
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• 제29권5C호
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• pp.716-725
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• 2004

본 논문에서는 VHLS 광학판 기반의 새로운 다시점 3D 디스플레이 시스템을 제시하였다. 즉, VHLS 광학판을 체적 홀로그램의 각 다중화 기록 특성을 이용하여 다시점 영상의 방향벡터를 회절격자 형태로 기록한 일종의 광방향 변조기로 제작한 다음, 제작된 VHLS을 LCD 공간광변조기에 부착되어 패널에 입력되는 다시점의 스테레오 영상을 각 시점에 해당하는 특정방향으로 분리해 줌으로써 다시점 3D 디스플레이 시스템을 실현하였다. 또한, 본 논문에서는 VHLS 광학판의 원리와 특성을 분석한 다음 상용 포토폴리머를 이용하여 최적화된 4시점의 VHLS 광학판을 설계 제작하고 이를 이용하여 4시점의 스테레오스코픽 3D 디스플레이 시스템을 구현하였다. 그리고 적응적 변위 추정 알고리즘으로 합성된 4시점의 테스트 영상을 이용한 광학실험을 통해 VHLS 기반의 다시점 3D 디스플레이 시스템의 구현 가능성을 제시하였다.

• 과학교육연구지
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• 제34권2호
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• pp.203-210
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• 2010

본 연구에서는 은염 물질인 Slavich PFG-01을 사용하여 투과형 홀로그래피 회절격자를 제작하고, 고효율의 회절격자 제작을 위한 현상액의 조성 등과 같은 화학적 처리 과정의 조건들을 파악하고, 반전표백과 무정착 은염 재생성 표백에 의한 회절격자의 회절 효율 특성에 대해 알아보았다. 현상액 AAC를 사용하여 반전표백에서 89.0%과 무정착 은염 재생성 표백에서 82.1%의 최대회절효율을 얻었으며, 무정착 은염 재생성 표백의 경우는 반전표백에 비해 높은 노출에너지가 필요함을 알 수 있었다. 기존의 홀로그래피 기록물질인 Agfa 8E75HD나 BB-640로 보고된 회절효율에 비해 더 높은 회절효율 얻을 수 있었으며, 기록물질 특성 차이로 인해 더 높은 노출에너지가 필요함을 알 수 있었다. 한 가지 현상 주약으로 이루어진 현상액에 비해 두가지 현상 주약을 혼합한 경우 더 높은 회절효율을 얻을 수 있었으며, 대체로 반전표백에 비해 무정착 은염 재생성 표백에서 높은 회절효율을 나타내었다.