Kunihiko Takano

Color electro-holographic display using a single white light source and a focal adjustment method

A new method for achieving a color electroholographic display has been developed and tested with promising results. In this method, holographic techniques that use a single white light source instead of the traditional three color lasers are employed. A metal halide lamp is used with each of the three color components required for reconstruction, which are extracted using cold mirrors. The separated color images are formed on three liquid-crystal display panels and are combined by a prism to form a single 3-D image. Image position is controlled by a focal adjustment method. Compared with the usual reconstruction methods that use three-color lasers, this new single-white-light approach appears to have improved color clarity.

Full-color electroholographic three-dimensional display system employing light emitting diodes in virtual image reconstruction

A full-color electroholographic 3-D display system employing LEDs is presented, and a virtual image reconstruction technique for it is studied. It is shown that the image blur observed in the reconstruction is suppressed to a lower level than in reconstruction employing a metal halide lamp. In addition, direct, independent drives on LEDs through RGB waves make the adjustment of white balance easier, and a wide viewing angle can be attained. Full-color, high-contrast 3-D images are obtained.

New type electro-holography system using LCDs

A new and practical method for achieving color electro-holographic display systems was developed and tested with very promising results. In proposal method, virtual image reconstruction method and color hologram reconstruction techniques utilizing a single white light source, instead of the traditional three color laser lights, and three liquid crystal display panels (LCD) were proposed.. In this method imaging lens is not necessary and we can get wide viewing angle. A metal halide lamp with good specifications in each wavelength of the color components was adopted as the light source. Each of the three color light components required for the reconstruction of an image was extracted by color separation using dichroic mirrors. The separated color images were then reconstructed by the hologram formed on the LCD panels which is then combined togethre through the use of a prism to form a single 3D image. As the result system become compact and realistic one.

Consideration of improvement of electro-holographic stereogram

Computer holographic stereogram (CHS) is useful for holographic 3D TV because it is constructed from the multi horizontal viewpoint plane images and is compatible to the multi camera stereoscopic image. Each hologram is recorded as a slit hologram (element hologram) but total viewing area and the number of the element holograms have been limited to some extent by the size and the resolution points of LCD. Therefore we used two LCDs for making CHS and deposited them horizontally and increased the viewing points to two times and extend the display area to satisfy the binocular parallax. We considered how viewing area becomes extended. We consider how we could improve the characteriostics of the images of CHS. We got moving images with this system using web-camera and also we considered the real time calculation about the hologram 3D-TV.

Three-Dimensional TV Using Holographic Stereogram

Computer holographic stereogram (CHS) is useful for holographic 3D TV because it is constructed from the multi camera horizontal viewpoint plane images and is compatible to the multi holographic stereogram image. Each hologram is recorded as a slit hologram (element hologram) but total viewing area and the number of the element holograms have been limited to some extent by the size and the resolution points of LCD panel. Therefore we used two LCDs for making CHS and deposited them horizontally and increased the viewing points to two times and extend the display area to satisfy the binocular parallax. We considered how viewing area becomes extended. We consider how we could improve the characteriostics of the images of CHS. We got moving images with this system using web-camera and considered the real time calculation about the hologram 3D-TV.

Large viewing angle projection type electro-holography using new type mist 3D screen

Recently, many type of 3-D displays are now being developed. We want to see 3-D moving image with comfortably and more expanded depth, Holography is different from the other 3-D display because natural stereoscopic image can be obtained. We have once developed a electro-holographic display using virtual image. But the viewing area is so small because the pixcel size of LCD is not so small. This time we developed the projection type electro-holographic display system. In the case of projection type holography [1], it needs to use the 3-D screen in order to project the reconstructed image clearly and viewing angle becomes wide. We developed the electro-holographic display system using mist 3-D screen. However, a reconstructed image with mist 3-D screen was flickered by gravity and flow of air. Then we considered to reduce the flicker of the image and we found that flicker could be reduced using flow controlled nozzle. Hence, at first we considered the most suitable shape of 3-D screen and then we constructed the array of flow controlled mist 3D screen. By the results of experiment we could get considerably high contrast 3-D moving image and get the viewing area more than 30°by this flow controlled nozzle attached new type mist 3-D screen and make clear the efficiency of this method.

Consideration of HMD-type holography 3D TV

In order to develop a holographic HMD-type holography 3D-TV with a full parallax, it seems to be very useful to study various techniques of virtual image reconstruction sufficiently. In this paper, a new, full color electro-holographic display system equipped with LED is presented. Virtual image reconstructing technique is applied, and full color, relatively highly contrasted 3D images are obtained using this system. We consider about the condition for realization of HMD-type holography 3D-TV using this technique because this techniques is very suitable for HMD system.

Transmission of hologram data and 3D image reconstruction using white LED light

Transmission of hologram is very important to realizing the holographic 3D TV. Transmission of Computer Generated Hologram(CGH) data using SSTV wire-less method was tried before and one frame with 76.8k bit data transmitted by 2kbbs was reported1-2). In this research we consider about more high speed transmission and more high resolution hologram data transmission and reconstruction using white LED.

High speed white LED light optical transmission for computer generated hologram (CGH)

Transmission of hologram is very important to realizing the holographic 3D TV. Transmission of Computer Generated Hologram(CGH) data using SSTV wire-less method is tried before and one frame with 76.8k bit data is transmitted by 2kbbs is reported1). In this research we consider to more high speed transmission and more high resolution hologram data transmission using white LED.

An elementary research on wireless transmission of holographic 3D moving pictures

In this paper, a transmitting process of a sequence of holograms describing 3D moving objects over the communicating wireless-network system is presented. A sequence of holograms involves holograms is transformed into a bit stream data, and then it is transmitted over the wireless LAN and Bluetooth. It is shown that applying this technique, holographic data of 3D moving object is transmitted in high quality and a relatively good reconstruction of holographic images is performed.