We have developed a multi-view image integration system which combines seven parallax video images into a single video image so that it fits the parallax barrier. The apertures of this barrier are not stripes but tiny rectangles that are arranged in the shape of stairs. Commodity hardware is used to satisfy a specification which requires that the resolution of each parallax video image is SXGA(1645×800 pixel resolution), the resulting integrated image is QUXGA-W(3840×2400 pixel resolution), and the frame rate is fifteen frames per second. The point is that the system can provide with QUXGA-W video image, which corresponds to 27MB, at 15fps, that is about 2Gbps. Using the integration system and a LCD display with the parallax barrier, we can enjoy an immersive live video image which supports seven viewpoints without special glasses. In addition, since the system can superimpose the CG images of the relevant seven viewpoints into the live video images, it is possible to communicate with remote users by sharing a virtual object.
The step barrier technology with multiple parallax images has overcome the problem of conventional parallax barrier system that the image quality of each image deteriorates only in the horizontal direction. The step barrier distributes the resolution problem both to the horizontal and the vertical directions. The system has a simple structure, which consists of a flat-panel display and a step barrier. The apertures of the step barrier are not stripes but tiny rectangles that are arranged in the shape of stairs, and the sub-pixels of each image have the same arrangement. And three image processes for the system applicable to computer graphics and real image have been proposed. Then, two types of 3-D displays were developed, 22-inch model and 50-inch model. The 22-inch model employs a very high-definition liquid crystal display of 3840 x 2400 pixels. The number of parallax images is seven and the resolution of one image is 1646 x 800. The 50-inch model has four viewing points on the plasma display panel of 1280 x 768 pixels. It can provide stereoscopic animations and the resolution of one image is 960 x 256 pixels. Moreover, the structural or electric 2-D 3-D compatible system was developed.
We have newly developed a few kinds of new auto-stereoscopic 3D displays adopting a ray-regenerating method. The method is invented basically at Osaka University in 1997. We adopted this method with LCD. The display has a very simple construction. It consists of LC panel with a very large number of pixels and many small light sources positioned behind the LC panel. We have examined the following new technologies: 1) Optimum design of the optical system. 2) Suitable construction in order to realize very large number of pixels. 3) Highly bright back-light system with optical fiber array to compensate the low lighting efficiency. The 3D displays having wide viewing area and being visible for plural viewers were realized. But the cross-talk images appeared more than we expected. By changing the construction of this system to reduce the diffusing factors of generated rays, the cross-talk images are reduced dramatically. Within the limitation of the pixel numbers of LCD, it is desirable to increase the pinhole numbers to realize the realistic 3D image. This research formed a link in the chain of the national project by NEDO (New Energy and Industrial Technology Development Organization) in Japan.
We have been developing the stereoscopic display using the Holographic Optical Element(HOE) for applying the new Head Mounted Display(HMD). The HOE is the grating that is made by Holography technique. It has the interference :fringe by two-laser beam interference method and its optical fimction can provide us with the binocular parallax images. We have already developed two kinds of stereoscopic displays using HOEs, one is the new HMO using the diverging HOE, and another is the Retinal Projection Display using the converging HOE. In this report, we will introduce the concept and experimental prototype of these displays.
First, we introduce the HOE which is very suitable for a combiner of the HMO. The only one piece of HOE recorded the interference fringe can separate the stereoscopic images onto each left and right eye. In addition, the visible rays through the HOE can be transparent with high intensity and the virtual images can be diffiacted with high efficiency. By using these optical characteristics of HOE, we accomplished the new HMO using the HOE that we can observe the real world with wide field of view and the virtual images with high intensity
Second, we propose the Retinal Projection Display. We completed the new optical system using the converging HOE that has the feature of the Maxwellian View. We can see the virtual images without our ocular accommodation because the focal dep1h of the image is extremely deep. The coherent parallel laser rays modulated by the Spatial Light Modulator(LCD or DMD) are converged at the center of the aystalline lens and they are projected on the retina directly. Th.is condition is same as the case of pan focus. If this characteristic is applied to the binocular condition, it is very suitable for binocular parallax stereoscopic display because the problem of the dissociation between accommodation and convergence may be solved
We have already proposed that we could realize the see- through HMD by using the Holographic Optical Elements (HOEs). The HMD using HOE we proposed so far is used the Maxwellian View, which is the direct projection on the human retina. When we see something by the Maxwellian View, we don't need the focusing of the crystalline lens (ocular accommodation) because the depth field is extremely wide. We have been estimated the optical characteristics of this HOE by using still images on the slide mount. In this report, we will show the prototype of Retinal Projection Display, which can provide us the electrical dynamic images on the electrical spatial light modulator.
A simple diffractive equation representing the Bragg condition is introduced from the pair of grating equations about thick hologram. Usually a color hologram is multiple exposured by 3 lasers; red, green, blue. Each fringe angle can be naturally equal to the others by adjusting 3 beams to the same direction. As the result every Bragg angle is the same value.
The authors propose new 3D display system using Holographic Optical Element (HOE) without glasses. The proposed HOE is used as holographic screen in this system. The HOE of proposed method can reconstruct white light in white illumination light. Namely, this HOE can reconstruct color images. The HOE has diffraction efficiency issue. However, we solved this issue, because we considered the Bragg condition when we made the HOE.
In recent years, the study of 3D-display is rapid development and many researchers propose many methods. Holography is best method. But, it is difficult that we developed holographic movie in the future tense. At the present time, stereogram method will make practicable in the near future. These methods can easily make animated 3D image. But this method has one problem; this method is conflict between convergence and accommodation. An observer can't watch 3D-display of this method long time. The authors will solve this problem. The authors proposed the 3D-display system that is used holography and stereogram technology. The proposed system has little conflict between convergence and accommodation. The authors developed this 3D-display system. The developed system has four focuses in horizontal direction. The display parts of the developed system are LCD display because the developed system can play 3D movie. Of cause, this display doesn't have special glasses. But, color of this display is single color. It is red. The authors will develop full color 3D-display. The picture size of this display is about 6 inch and the form of this display is very large. The author will develop small size system and show large size picture.
KEYWORDS: Holographic optical elements, Head-mounted displays, Virtual reality, Eye, Retina, Holography, Human vision and color perception, Prototyping, Crystals, Head
We will discuss the characteristics of the Head Mounted Display (HMD) using Holographic Optical Element (HOE) in this paper. We have already proposed that using the HOE we could realize the see-through HMD, that is to say the binocular stereoscopic display. This time we evaluate the influence on the human vision system regarding the optical characteristics of the HOE. The HMD using HOE we proposed so far is the Maxwellian View which is the direct projection on the human retina. When we see something by Maxwellian View, we don't need the focusing of the crystalline lens (ocular accommodation) because the depth field is extremely wide. Therefore our binocular crystalline lens will focus at the vergence point when the Maxwellian View is used on the binocular retina. And we can solve the dissociation of accommodation and convergence which is the basic problem of the conventional HMD. We have made the prototype of HOE which can provide the Maxwellian View on our retina and we have proved that our HOE could separate the binocular images onto left and right eye. In this report, we will introduce the Maxwellian View will change the ocular accommodation optionally according to the convergence when we see the real objects and the virtual objects at the same time. We proved that the HOE which provided the Maxwellian View could solve the dissociation of accommodation and convergence.
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.
We will discuss the prototype of Head Mounted Display using Holographic Optical Element in this paper. It is obvious that a single HOE can record the multiple optical images by the characteristic in itself, that is angular selectivity and wavelength selectivity. Therefore, it is very easy to understand the HOE has the function which can separate the stereoscopic images onto the left and right eyes, like as the conventional HMD. In this report, we propose the prototype of HMD using a single HOE, and we will extract the problem in application of the real industrial field, especially manufacturing and designing. Consequently, we proved that the HMD using Lippmann hologram has the potentiality of miniaturization, lightening, wide field of vision. This HMD can be suitable in the Virtual Reality field. But it is necessary to adjust the pupil distance and the incident angle of conjugate beam precisely.
We have been making researches on 3D displays using computer-generated holograms (CGHs). We use an image setter with a resolution of 5080 dots per inch to record the binary CGH patterns. It is possible to reconstruct CGHs with light- emitting diodes or light bulbs which have small emitting segments. In the reconstruction with a light bulb, color- smeared images are observed due to the white light. In order to improve this dispersion, we considered a method to apply a color filter to the CGH. And, we propose a method to make computer-generated color hologram which can reconstruct color point light sources, by combining RGB color filters with the stripe CGHs corresponding to each color.
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.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.