Automotive augmented reality 3D head-up display based on light-field rendering with eye-tracking.

We explore the feasibility of implementing stereoscopy-based 3D images with an eye-tracking-based light-field display and actual head-up display optics for automotive applications. We translate the driver's eye position into the virtual eyebox plane via a "light-weight" equation to replace the actual optics with an effective lens model, and we implement a light-field rendering algorithm using the model-processed eye-tracking data. Furthermore, our experimental results with a prototype closely match our ray-tracing simulations in terms of designed viewing conditions and low-crosstalk margin width. The prototype successfully delivers virtual images with a field of view of 10° × 5° and static crosstalk of <1.5%.

Autostereoscopic 3D display using directional subpixel rendering.

In this paper we present an autostereoscopic 3D display using a directional subpixel rendering algorithm in which clear left-right images are expressed in real time based on a viewer's 3D eye positions. In order to maintain the 3D image quality over a wide viewing range, we designed an optical layer that generates a uniformly distributed light field. The proposed 3D rendering method is simple, and each pixel processing can be performed independently in parallel computing environments. To prove the effectiveness of our display system, we implemented 31.5" 3D monitor and 10.1" 3D tablet prototypes in which the 3D rendering is processed in the GPU and FPGA board, respectively.

Sampling and error analysis of radial symmetric interpolation for fast hologram generation.

In this paper, we present a fast hologram pattern generation method by radial symmetric interpolation, which exploits concentric redundancy of a point hologram pattern to reduce computational complexity in hologram pattern calculation, and analyze the quality degradation sources in the proposed method. Compared to the analytic method in which phase and amplitude information is directly calculated from a wave equation, in our method a Fresnel zone plate is periodically sampled along a diagonal line and the wave information of a point hologram is calculated by linear interpolation. During these sampling and interpolation processes, the wave information can be modified from the original signal and the reconstruction quality can be degraded compared to the analytic pattern calculation method. The effects of sampling and linear interpolation are investigated in spatial and frequency domains.

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.

Multiple ray cluster rendering for interactive integral imaging system.

In this paper, we present an efficient Computer Generated Integral Imaging (CGII) method, called multiple ray cluster rendering (MRCR). Based on the MRCR, an interactive integral imaging system is realized, which provides accurate 3D image satisfying the changeable observers' positions in real time. The MRCR method can generate all the elemental image pixels within only one rendering pass by ray reorganization of multiple ray clusters and 3D content duplication. It is compatible with various graphic contents including mesh, point cloud, and medical data. Moreover, multi-sampling method is embedded in MRCR method for acquiring anti-aliased 3D image result. To our best knowledge, the MRCR method outperforms the existing CGII methods in both the speed performance and the display quality. Experimental results show that the proposed CGII method can achieve real-time computational speed for large-scale 3D data with about 50,000 points.

3D Display Calibration by Visual Pattern Analysis.

Nearly all 3D displays need calibration for correct rendering. More often than not, the optical elements in a 3D display are misaligned from the designed parameter setting. As a result, 3D magic does not perform well as intended. The observed images tend to get distorted. In this paper, we propose a novel display calibration method to fix the situation. In our method, a pattern image is displayed on the panel and a camera takes its pictures twice at different positions. Then, based on a quantitative model, we extract all display parameters (i.e., pitch, slanted angle, gap or thickness, and offset) from the observed patterns in the captured images. For high accuracy and robustness, our method analyzes the patterns mostly in the frequency domain. We conduct two types of experiments for validation; one with optical simulation for quantitative results and the other with real-life displays for qualitative assessment. Experimental results demonstrate that our method is quite accurate, about a half order of magnitude higher than prior work; is efficient, spending less than 2s for computation; and is robust to noise, working well in the SNR regime as low as 6dB.