Ken Mashitani

Step barrier system multiview glassless 3D display

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.

Multiview image integration system for glassless 3D display

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 Liquid Crystal 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.

Influence of 3‐D cross‐talk on qualified viewing spaces in two‐ and multi‐view autostereoscopic displays

— To estimate the qualified viewing spaces for two- and multi-view autostereoscopic displays, the relationship between image quality (image comfort, annoying ghost image, depth perception) and various pairings between 3-D cross-talk in the left and right views are studied subjectively using a two-view autostereoscopic display and test charts for the left and right views with ghost images due to artificial 3-D cross-talk. The artificial 3-D cross-talk was tuned to simulate the view in the intermediate zone of the viewing spaces. It was shown that the stereoscopic images on a two-view autostereoscopic display cause discomfort when they are observed by the eye in the intermediate zone between the viewing spaces. This is because the ghost image due to large 3-D cross-talk in the intermediate zone elicits different depth perception from the depth induced by the original images for the left and right views, so the observers depth perception is confused. Image comfort is also shown to be better for multi-views, especially the width of the viewing space, which is narrower than the interpupillary distance, where the parallax of the cross-talking image is small.

54.3: SXGA Non-Glasses 3-D Displays with New Image Splitter Head Tracking System

16″ and 18″ SXGA non-glasses 3-D displays are newly developed. Those displays are equipped with new head tracking system, consisting of electrically movable LC image splitter and CCD camera, which enlarges stereoscopic viewing area. Those displays are compatible with 2-D images by eliminating the effect of image splitter electrically.

23.3: Characterization of 3D Image Quality on Autostereoscopic Displays — Proposal of Interocular 3D Purity —

We propose “Interocular 3D Purity”; a quantitative measure of the image quality of stereoscopic displays. This measure expresses how well stereopsis-disturbing images are excluded. We apply this measure to three types of display and find it to be effective in analyzing not only the dimensions of stereoscopic viewing spaces but also the smoothness of motion parallax.

44.3: Characterization of Motion Parallax on Multi-view/Integral-imaging Displays

Multi-view and integral imaging displays have a significant feature that allows people to induce better stereopsis due to motion parallax. Base on the analysis of the mechanism, we propose characterization methods of the displays. Our methods evaluate change in luminance of stereoscopic images when observers eye positions are displaced. The results show that our methods are good for showing smoothness of the motion parallax.

Floor-projected 3D system by 3D ready ultra short throw distance projector

This paper introduces a floor-projected 3D system and a related viewing style, face to face style 3D projection. The floor-projected 3D system, which is built on the ultra short throw distance projector, creates realistic 3D vision on the floor surface, meanwhile avoid shadow interference. And face to face style 3D projection is capable to display proper 3D image to observers on two sides of the projection area.

8.2: Color Tuning Projection System for Adaptive Combination of High Brightness and Wide Color Gamut

We have developed a new projector with a fourth liquid crystal panel that controls yellow light separately from RGB lights of UHP lamp. This additional panel system enables projector to achieve adaptive control of both high brightness and 120% wide color gamut. In this paper, we propose the innovative design concept and the technical development of the Color Tuning Projection System and represent the characteristics of the prototype.

Development of a color 3D display visible to plural viewers at the same time without special glasses by using a ray-regenerating method

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.

Color‐tuning projection system for adaptive combination of high brightness and wide color gamut

— The demand for projectors with high brightness and wide color gamut has been increasing; however, UHP lamp projectors cannot deliver those two qualities efficiently and simultaneously because of its color-separation system. The newly developed projection system — “Color-Tuning Projection System” — realizes the adaptive combination of high brightness and wide color gamut with one projector. This projector features a fourth liquid-crystal panel — “Color Tuner” — with a 3LCD optical engine, which controls yellow light separately from the RGB light of a UHP lamp. This color-tuner-based optical engine — “Color-Tuning Optical Engine” — and a new color-conversion signal-processing algorithm — “Adaptive Color Conversion Algorithm” — controls the yellow-light volume and corrects color-shifted pixels according to the brightness and chromaticity analysis of the input image, key technologies of the Color-Tuning Projection System. This additional panel system enables the projector to ach ieve up to 115% higher brightness and 120% wider color gamut according to the input image. This paper presents an innovative design concept, a novel technology regarding brightness and a color-gamut conversion projection system, and the characteristics of the prototype.