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Recently, because the high-speed network system known as broadband internet has become widespread, it is now possible to transmit various forms of multimedia data using this system. We found several research reports for the transmitting visual images in the network streaming process. However, there seemed to be few reports on transmission of holographic 3D movies. We present a transmitting process of holographic 3D movies adopting network-streaming techniques and a hologram in which 3D objects were recorded as fringe patterns. When we applied this method, we could achieve excellent transmission of holographic 3D movies.Moreover, we could reconstruct good holographic images using transmitted streaming data. From this result, it seemed possible to develop new transmitting processes of 3D moving data using well-known conventional techniques.

Electro holography is a technique that can reconstruct moving color 3D images. Recently, several methods using a white light source or laser waves have been tested. However, since the reconstructing waves are applied closely approximated to the plane waves, the system tends to be very complicated and, hence, difficult to make smaller. In this paper, we examine a virtual image observing process using LED as a reference beam and analyze the color characteristics of the process. The results showed excellent color characteristics.

Holographic process is an imaging technique for reconstructing 3D images in three dimensional space. In holographic wave front reconstructing, several approaches adopting photorefractive crystals or lens systems have been studied. However in these systems, the problems arise such that the size of the reconstructed image is to be small and the visual field is restricted to be narrow by the lens. Our new imaging process presented here takes advantage of scattering of particles (by spraying water) as a holographic 3D screen, and this process enables us to reconstruct relatively larger 3D images (5cm×5cm) than the ones (1.5cm×1.5cm) observed in the previous systems

We investigated the basic white-light optical process for the reconstruction of encoded color holographic images by using liquid crystal display (LCD) panels. Instead of using three lasers, we used a metal halide lamp as the only white-light source. The lamp had good characteristics in each band of the wavelengths of the color components. Light components neaded for the reconstruction of images were extracted by color separation using dichroic mirrors, and then, color stereographic images were reconstructed by composing the lights filtered out by a hologram pattern formed on the LCD panels through prisms. As a result, several fine color stereographic images were reconstructed in our optical system equipped with a white-light source and LCD panels.

Attention is being paid to computer generated holograms (CGH) that can be formed by liquid crystal devices (LCD) because of their possible applications in electro-holography. In the research reported here the kinoform of an on-axis type CGH was constructed by using a commercially available TN type LCD as phase modulator, and the basic characteristics of its image were examined. Moreover an electro-holography system for color 3D animated image display was developed by using three LCD panels, RGB three lasers and graphics frame memory. A clear color image was reconstructed by taking into account the wavelength dependence of the size and position of the color image, then the characteristics of color gamut and animation of the reconstructed color image were evaluated in order to determine the feasibility of this system for electro-holography.

ホログラフィは以前から静止画像のディスプレイとして用いられて来た.その自然な立体感のために動画像を対象とした3次元画像表示装置として期待され, そのための研究が行われて来た.しかし, 動画ホログラフィの実現のためには, 記録材料および表示デバイスなどの要素技術の開発や情報量の圧縮など, 様々な問題の解決が必要である.ここでは内外で現在活発に行われつつある動画ホログラフィの研究についての動向を報告する.

本論文では動く物体に対するホログラムの作成・伝送およびその像再生を行うホログラフィテレビジョンの実現に向けて基礎実験システムを作成し, その特性について検討を行った.すなわち, 動画像として文字物体を用いて, 平面参照光との干渉によりテレビジョンの受光面に直接ホログラムを作成し, 次にそれを電気信号に変換した後にテレビ信号の伝送系を用いて伝送し, 液晶表示デバイス (LCD) を用いて実時間で再生像を得ることができた.また, 文字物体を動かすと再生像の位置もほぼリアルタイムに移動することを確認した.さらに, 空間フィルタを用いて0次透過光および高次回折光を取り除くことができた.これらの結果から, ホログラフィテレビジョンの基礎的な動作を確認でき, 本研究の有効性を明らかにすることができた.