Juyong Park

Optimal projector configuration design for 300-Mpixel multi-projection 3D display

To achieve an immersive natural 3D experience on a large screen, a 300-Mpixel multi-projection 3D display that has a 100-inch screen and a 40° viewing angle has been developed. To increase the number of rays emanating from each pixel to 300 in the horizontal direction, three hundred projectors were used. The projector configuration is an important issue in generating a high-quality 3D image, the luminance characteristics were analyzed and the design was optimized to minimize the variation in the brightness of projected images. The rows of the projector arrays were repeatedly changed according to a predetermined row interval and the projectors were arranged in an equi-angular pitch toward the constant central point. As a result, we acquired very smooth motion parallax images without discontinuity. There is no limit of viewing distance, so natural 3D images can be viewed from 2 m to over 20 m.

Generating vivid colors on red-green-blue-white electonic-paper display

Color characteristics of an RGBW (red, green, blue, white) electrophoretic display (EPD) prototype developed by Samsung Electronics are analyzed. EPD shows strong crosstalk between subpixels because of both the fringe field between subpixels and the scattering phenomena at the display surface. An RGB-to-RGBW color-decomposition algorithm optimized to EPD characteristics is developed that compensates for color deterioration due to the fringe field and scattering phenomena. For the four-color-decomposition algorithm, white is added to the primary colors to enhance the reflectance of the vivid colors while minimizing chroma loss. The psychophysical experimental result shows that images rendered with the algorithms developed in this study are preferred more than 90% of the time over those rendered with algorithms from previous studies. This research proves that, in spite of the limited physical property of EPD, the color quality can be improved dramatically through the use of well-designed color-rendering algorithms.

61.4: Active Crosstalk Reduction on Multi‐View Displays Using Eye Detection

Multi-view displays have some problems in the quality of images, while they provide glasses-free systems. Especially inter-view crosstalk is the most critical factor to deteriorate the image quality and cause visual fatigue under large depths. We propose a method to provide clear images appropriate to the positions of the observers eyes. In a subpixel group, using the visibility profiles of the subpixels expressing each view, we can determine the subpixel values to express a certain color at a certain direction. This can compensate color distortion caused by slanted lenticular lens and expand the observable area using the repeated regions neighboring the main region.

Autostereoscopic 3D — How can we move to the next step?

The 3DTV market has already started and more people have been enjoying new visual experience. But annoyance of wearing 3D glasses is a problem and the autostereoscopic display still has several limitations unsolved. This presentation discusses these limitations and our approaches to overcome them.

Eye Tracking based Glasses-free 3D Display by Dynamic Light Field Rendering

Glasses-free 3D display is developed using dynamic light field rendering algorithm in which light field information is mapped in real time based on 3D eye position. We implemented 31.5″ and 10.1″ prototypes.

Color and brightness uniformity compensation of a multi-projection 3D display

Light-field displays are good candidates in the field of glasses-free 3D display for showing real 3D images without decreasing the image resolution. Light-field displays can create light rays using a large number of projectors in order to express the natural 3D images. However, in light-field displays using multi-projectors, the compensation is very critical due to different characteristics and arrangement positions of each projector. In this paper, we present an enhanced 55- inch, 100-Mpixel multi-projection 3D display consisting of 96 micro projectors for immersive natural 3D viewing in medical and educational applications. To achieve enhanced image quality, color and brightness uniformity compensation methods are utilized along with an improved projector configuration design and a real-time calibration process of projector alignment. For color uniformity compensation, projected images from each projector are captured by a camera arranged in front of the screen, the number of pixels based on RGB color intensities of each captured image is analyzed, and the distributions of RGB color intensities are adjusted by using the respective maximum values of RGB color intensities. For brightness uniformity compensation, each light-field ray emitted from a screen pixel is modeled by a radial basis function, and compensating weights of each screen pixel are calculated and transferred to the projection images by the mapping relationship between the screen and projector coordinates. Finally, brightness compensated images are rendered for each projector. Consequently, the display shows improved color and brightness uniformity, and consistent, exceptional 3D image quality.

Inversion-free multiview subpixel rendering for natural 3D presentation

In this paper, an inversion-free subpixel rendering method that uses eye tracking in a multiview display is proposed. The multiview display causes an inversion problem when one eye of the user is focused on the main region and the other eye is focused on the side region. In the proposed method, the subpixel values are rendered adaptively depending on the eye position of the user to solve the inversion problem. Also, to enhance the 3D resolution without the color artifact, the subpixel rendering algorithm using subpixel area weighting is proposed instead of the pixel values. In the experiments, 36-view images were seen using active subpixel rendering with the eye tracking system in a four-view display.

Feasibility of Eye-tracking based Glasses-free 3D Autostereoscopic Display Systems for Medical 3D Images

Medical image diagnosis processes with stereoscopic depth by 3D display have not been developed widely yet and remain understudied Many stereoscopic displays require glasses that are inappropriate for use in clinical diagnosis/explanation/operating processes in hospitals. An eye-tracking based glasses-free three-dimensional autostereoscopic display monitor system has been developed, and its feasibility for medical 3D images was investigated, as a cardiac CT 3D navigator. Our autostereoscopic system uses slit-barrier with BLU, and it is combined with our vision-based eye tracking system to display 3D images. Dynamic light field rendering technique is applied with the 3D coordinates calculated by the eye-tracker, in order to provide a single viewer the best 3D images with less x-talk. To investigate the feasibility of our autostereoscopic system, 3D volume was rendered from 3D coronary CTA images (512 by 512 by 400). One expert reader identified the three main artery structures (LAD, LCX and RCA) in shorter time than existing 2D display. The reader did not report any eye fatigue or discomfort. In conclusion, we proposed a 3D cardiac CT navigator system with a new glasses-free 3D autostereoscopy, which may improve diagnosis accuracy and fasten diagnosis process.