Kunio Sakamoto

New approach to the real-time 3D display using a holographic optical element

A display system requiring no special glasses is a useful technology for 3D images. In this paper, two types of real- time 3D displays using a holographic screen instead of a lenticular screen are described. One is a stereoscopic 3D display system with viewing apertures such as conventional two-step holographic stereogram. The other is a stereoscopic 3D display system based on a reconstruction of parallax- rays. These systems consist of a liquid crystal device and a holographic screen formed on holographic optical elements. These systems can construct animated 3D images in real-time by updating LCD pixels.

Real-time three-dimensional display using a holographic optical element

The holography is a useful technology for 3D images. There are two types of the hologram in the reconstruction; one is a transmission-type and the other is a reflection-type. Especially, the reflection-type hologram that can be hanging on the wall is convenience because it needs no space. Mark Shires presented a flat panel real-time holographic stereogram in his paper. However, his display is unquestionably a transmission-type. In this paper, a 3D real-time display with a holographic optical element (HOE) is described. This display is realized both the transmission-type and the reflection-type. The diffraction efficiency becomes better because this display has a single HOE. This simple 3D display is ideal for both consumer and industrial use.

Image Sensing Technology. Monocular Multi-view Stereoscopic Image Capturing Camera.

A 3-D head-mounted-display (HMD) system is useful for constructing a virtual space. We have developed a 3-D HMD system with a monocular stereoscopic display. This paper describes a stereoscopic image capturing camera that uses the camera position shifting optics to capture monocular stereoscopic images. It also describes the characteristics of spatial reconstruction when the parallax interval and viewing angle have been changed.

Monocular Stereoscopic 3-D Display System.

A 3-D head mounted display (HMD) system is useful for constructing a virtual space. We have developed a 3-D HMD system. Traditional displays have drawbacks in that the lightness of real and virtual images is insufficient for spatial viewing. This problem can be solved by using the simultaneous perception of the human vision and a 3-D vision system. We also describe a newly developed monocular stereoscopic 3-D display system for a 3-D HMD system.

Three-dimensional display systems with holographic technologies

Holography is a useful technology for 3D images. The authors have researched spatial imaging based on a holographic technology. This paper describes many good results of fundamental study about 3D electronic images--3D TV monitor, 3D fine art, 3D measuring instrument and so on. In addition, this paper presents the latest result of our study about a stereoscopic 3D display system. This system consists of a liquid crystal device and a holographic screen formed of holographic optical elements. This display can construct animated 3D images in real-time by updating LCD pixels.

Holographic stereogram movie system for practical 3D display

A display system requiring no special glasses is a useful technology for 3D images. The authors have researched real- time holographic stereogram displays using a holographic screen. In June 1995, we presented the stereoscopic 3D display system with viewing apertures such as conventional two-step holographic stereogram. In 1996, we introduced the stereoscopic 3D color display system using a holographic pseudo-color technique. Last year at the 1997 conference on Practical Holography, the authors presented the stereoscopic 3D display system based on a reconstruction of parallax- rays. These systems consist of a liquid crystal device and a holographic screen formed of holographic optical elements. These systems can construct animated 3D images in real-time by updating LCD pixels. In this paper, the latest result of our study about a stereoscopic 3D display system is proposed. In addition, this paper presents the result of a holographic stereogram movie system as a future 3D display.

Real-time 32-view Stereoscopic 3-D Display System Using a Holographic Screen.

A real-time stereogram display system using a holographic optical element is one of the most useful technologies providing 3-D images because it is simple and does not require the use of special glasses. This kind of display substitutes a holographic lenticular screen for a conventional refractive lenticular screen. We have developed a prototype system based on the stereoscopic principle of reconstructing parallax rays. The trial holographic screen of this display is 50 cells by 40 cells (i. e., it contains 2000 holographic grating cells). Every grating cell consists of 32 various holographic diffraction gratings, so each cell is capable of reconstructing 32 uni-directional parallax rays. This display system can thus present a 3-D image having 50 pixels for horizontally and 40 pixels for vertically (each pixel has 32 horizontal parallaxes).

Real-time 3-D Color Display Using a Holographic Optical Element.

A display system requiring no special glasses in a useful technology for three-dimensional (3-D) images. The lenticular display system has demerits such as a non-planar screen and blurred images. In this paper, a new 3-D real-time color display with a holographic optical element (HOE) is described. This simple 3-D display can improve the above-mentioned problems. The advantage of the HOE screen is that the number of presented views is much greater than the number of presented views of an equivalent lenticular display, because the HOE screen can multiplex pixels both horizontally and vertically to display lateral views. This color screen can be made easily and smoothly in the same way as the monochrome screen. The trial HOE screen is 4″×5″ and consists of 384, 000 holograms Therefore, the image size measures approximately 4″×5″, and the resolution is 200×160 pixels×4 views×3 (RGB).

Applications of holographic stereograms by a large liquid crystal display

A fabrication method for holographic stereograms using a large liquid crystal display panel (LCD) is proposed and experimental results are described. Holographic stereogram is a useful method that can synthesize computer graphics or portraits of 2D perspectives but its process is troublesome. An LCD of a lap top personal computer is applied for perspective display. This method has some advantages, e.g., simple optical layout, no registration mechanism, no aberration by projection lenses and so on. A technique to improve the quality of holograms with a holographic optical element is also proposed.