• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.31A no.12
• /
• pp.71-79
• /
• 1994

In this paper, $As_{40}Se_{50-x}S_[x}Ge_{10}$(x=0, 25, 35, at.%) bulk and thin films, to develope device of reversible hologram, proved amorphous by X-RD analysis. On the thin films with composition rate, as Se-doped-quantity increased, absorption edge shifted to long wavelength, and we found that reversible photodarkening effect occurred when thin films are exposed and annealed. Optical energy gap was larger when thin films are annealed than exposed. In this effect thin films structurally stabilized by annealing. It is to formed grating hologram by the bragg method on the $As_{40}Se_{15}S_[35}Ge_{10}$ thisn films with the best transmittance properties As polariging angle grew larger, we found that maximum diffraction efficiency became smaller, and obtained it of 4.5% on the thin fim thicknesss of 0.6 m, polarizing angle of 40$^[\circ}$ and exposing for 20sec.

• Korean Journal of Optics and Photonics
• /
• v.14 no.1
• /
• pp.65-71
• /
• 2003

To maximize the storage density in a localized hologram recording method, each hologram should be recorded as close as possible to its neighboring holograms. In this case, the reference beams used to record two adjacent holograms may overlap in spatial multiplexing. Through simulations and experiments, we show that there exists an optimal reference beam size to minimize the overlap for a given shifting distance of the reference beams in spatial multiplexing. Thus the advantages of the localized hologram recording method can be minimally sacrificed while the storage density is increased.

• Journal of Korea Game Society
• /
• v.18 no.3
• /
• pp.79-86
• /
• 2018

Hologram that usually used in modern art performance and movie, is now also used in different area such as architecture, car design, IT, medicine, design and different types of multi-media art performance. This study is to analyze how hologram works in stage production and affect in variety types of art performance and also how it affects in future art performance.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.7C
• /
• pp.540-547
• /
• 2008

In this paper, we proposed a new VLSI architecture which can generate computer-generated hologram (CGH) in real-time and implemented to hardware. The modified algorithm for high-performance CGH was introduced and re-analyzed (or designing hardware. from both numerical and visual analysis, the infernal number system of hardware was decided. CGH algorithm and precision analysis enabled to propose a new cell architecture for CGH. The operational sequence was analyzed with the architecture of CGH cell and the characteristics of the modified CGH algorithm, and finally the pipelined architecture and the operational timing were proposed.

• Journal of the Optical Society of Korea
• /
• v.13 no.1
• /
• pp.92-97
• /
• 2009

In this paper, a conventional simulated annealing (SA) method for optimization of a kinoform computer generated hologram (CGH) is analyzed and the SA method is modified to reduce a reconstruction error rate (ER) of the CGH. The dependences of the quantization level of the hologram pattern and the size of the data on the ER are analyzed. To overcome saturation of the ER, the conventional SA method is modified as it magnifies a Fourier-transformed pattern in the intermediate step. The proposed method can achieve a small ER less than 1%, which is impossible in the conventional SA method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.24 no.6
• /
• pp.440-444
• /
• 2011

We have analyzed electrical characteristics of spot light solar cell modules and have completed fabrication of spot light solar cell modules. Before we test modules, we have carried about UV test of hologram. As a result of test, we have obtained 165% efficiency of hologram film. the other hand, we obtained 75% efficiency of general films. After we have fabricated solar modules and carried about field test, spot light solar cell modules with hologram have been investigated 17.3 A of Isc and 155.4 W of power.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2018.05a
• /
• pp.553-554
• /
• 2018

최근 AI, 음성인식, 빅데이터, IoT의 발달에 의해 홈 스마트 비서에 대한 관심이 증대되고 있다. 이에 맞추어 국내외 대기업들은 청각 중심의 다양한 스마트 비서 제품을 출시하였다. 따라서 본 논문에서는 기존의 단점을 보완한 스마트-홈 비서 시스템을 제안한다. 스마트-홈 비서 시스템은 전방 상황 및 사용자의 행동을 인식할 수 있게 하는 영상 처리부, 카메라에서 획득한 정보에 따라 상황에 맞추어 Pseudo-Hologram 콘텐츠를 재생하는 영상 표출부로 구성되어 있다. Pseudo-Hologram을 활용하여 표출함으로써 사용자 UI/UX에 실감성을 더한 시각적인 스마트-홈 비서 시스템을 구현하였다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.4
• /
• pp.603-610
• /
• 2008

In this paper, we propose an efficient noise reduction algorithm for digital hologram during acquisition and transmission. The proposed algorithm segment a digital hologram with object region and background region after DCT. Then, we adopt a histogram transition method for object region and zero-value change method for background region. The experimental results show that our algorithm has beuer performance than a natural image denoising algorithm.

• Electronics and Telecommunications Trends
• /
• v.34 no.6
• /
• pp.145-155
• /
• 2019

Holography is a technique that can acquire and reproduce 3D objects nearly perfectly by representing both the amplitude and phase of light. Recently, digital holography has received considerable attention because it is simpler than analog holography from acquisition to reproduction. The data size of the digital hologram increases tremendously as the quality of digital holograms depends on their pixel pitch and resolution. Hence, efficient compression is necessary to realize holographic imaging services. In this report, we introduce recent digital hologram compression techniques and JPEG Pleno holography, which is the first international standardization activity for digital hologram compression. Furthermore, we discuss the future of this field.

• Journal of the Optical Society of Korea
• /
• v.12 no.4
• /
• pp.269-274
• /
• 2008

We propose a new synthesis method for the hologram of 3D objects using incoherent multiple orthographic view images. The 3D objects are captured and their multiple orthographic view images are generated from the captured image. Each orthographic view image is numerically overridden by the plane wave propagating in the direction of the corresponding view angle and integrated to form a point in the hologram plane. By repeating this process for all orthographic view images, we can generate the Fourier hologram of the 3D objects.