Kunyang Li

Full Resolution, Low Crosstalk, and Wide Viewing Angle Auto-Stereoscopic Display With a Hybrid Spatial-Temporal Control Using Free-Form Surface Backlight Unit

A full resolution, low crosstalk and wide viewing angle auto-stereoscopic display is demonstrated with the use of a novel free-form surface backlight (FFSB) technique, in conjunction with a hybrid spatial and temporal control scenario. The overall crosstalk coming from adjacent channels is shown to be lower than 5% even at a wide viewing angle, and minimum achievable crosstalk can be as small as 2.41%. The key element design giving rise to achieving the full viewing angle greater than 45 degrees is also presented.

Visual effect of a linear Fresnel lens illuminated with a directional backlight.

A linear Fresnel lens illuminated by a directional backlight is studied. The light distribution on the lens surface visualized by a retina is simulated with a Monte Carlo ray-tracing technique, and the visualized display uniformity on the lens surface is found to depend critically on the lens quality as well as on the viewing position away from the light propagation axis. The effect of the light source configuration as well as the deviation of the microstructures of the Fresnel lens from ideal structure are studied. The simulation is verified with an experimental study, and good agreement between numerical and experimental results is obtained. Design guidelines are presented for a backlight-illuminated system to achieve high-quality uniform flat-panel two-dimensional and autostereoscopic displays.

Simulation and Control of Display Uniformity in a Backlight Illuminated Image Array

The relative retinal illumination (RRI) distribution of a display system consisting of arrayed backlight units, focusing lenses, and viewing screen is simulated with Monte Carlo ray tracing method. A random scattering model is applied to describe the optical seam effect in the vicinity of the stitching. RRI distribution on the screen viewed at different locations for an autostereoscopic display system is simulated, giving rise to a quantitative description of display inhomogeneity on the screen. The method to achieve a uniform RRI distribution on the screen is proposed. The numerical simulation is tested with experimental verification, and good agreement is obtained. The simulation, experiment, and measurement can be applied as design guidelines for autostereoscopic display, integrated imaging display, and other novel backlight illuminated optical systems.

Optimizing display uniformity with a staggered backlight in an autostereoscopic display system

In this paper, we propose a staggered design directional backlight system in an autostereoscopic display. Currently, one of the main deficiency of autostereoscopic display is low display uniformity in both horizon and depth direction. In order to optimized display unifomity, the system mainly employs a staggered backlight array designed by a trace-back algorithm and a light shaping diffuser. As result, the horizontal dark areas are fully compensated. Moreover, crosstalk of experimental system is as low as 0.9%.

A high performance auto-stereoscopic display based on free-form surface backlight array and mix-teeth Fresnel lens

An ultra HD, low crosstalk, high luminance uniformity, and wide field of view auto-stereoscopic display is demonstrated with the use of novel free-form surface backlight array (FFSBA) and mix-teeth Fresnel lens (MTFL) technology, in conjunction with a hybrid spatial and temporal control scenario. The luminance uniformity is shown to be higher than 95.3% even within a wide viewing angle, and the minimum achievable crosstalk can be as small as 2.2%. The moiré pattern is avoided by an equivalent anisotropic film (EAF).

Virtual reality and motion sensing conjoint applications based on stereoscopic display

To demonstrate the feasibility and compatibility of virtual reality and motion sensing conjoint applications, a visual keyboard system is presented. In the method, when a viewer is touching the stereoscopic keyboard image in air, the system can reconstruct the position of the fingertip, output the information on the screen in real-time. This system has been demonstrated fine compatibility in skin color, ambient light and viewing angle. Moreover the point-cloud gesture control system and the visual drawing/writing scketchpad system are provided which shows the diversity of conjoint applications.

Simulation approach of display uniformity in a backlight illuminated lens array

The relative retinal illumination (RRI) distribution of a display system consisting of arrayed backlight units, focusing lenses and viewing screen is simulated with Monte Carlo ray tracing method. A random scattering model is applied to describe the optical seam effect in the vicinity of the stitching. RRI distribution on the screen viewed at different locations for an directional backlight display system is simulated, giving rise to a quantitative description of display inhomogeneity on the screen. The method to achieve a uniform RRI distribution on the screen is proposed. The numerical simulation is tested with experimental verification and good agreement is obtained. The simulation, experiment and measurement can be applied as design guidelines for autostereoscopic display, integrated imaging display and other novel backlight illuminated optical systems.

Directional backlight liquid crystal autostereoscopic display: technical challenges, research progress, and prospect(Conference Presentation)

Recent upsurge on virtual and augmented realities (VR and AR) has re-ignited the interest to the immerse display technology. The VR/AR technology based on stereoscopic display is believed in its early stage as glasses-free, or autostereoscopic display, will be ultimately adopted for the viewing convenience, visual comfort and for the multi-viewer purposes. On the other hand, autostereoscopic display has not yet received positive market response for the past years neither with stereoscopic displays using shutter or polarized glasses. We shall present the analysis on the real-world applications, rigid user demand, the drawbacks to the existing barrier- and lenticular lens-based LCD autostereoscopy. We shall emphasize the emerging autostereoscopic display, and notably on directional backlight LCD technology using a hybrid spatial- and temporal-control scenario. We report the numerical simulation of a display system using Monte-Carlo ray-tracing method with the human retina as the real image receiver. The system performance is optimized using newly developed figure of merit for system design. The reduced crosstalk in an autostereoscopic system, the enhanced display quality, including the high resolution received by the retina, the display homogeneity without Moiré- and defect-pattern, will be highlighted. Recent research progress including a novel scheme for diffraction-free backlight illumination, the expanded viewing zone for autostereoscopic display, and the novel Fresnel lens array to achieve a near perfect display in 2D/3D mode will be introduced. The experimental demonstration will be presented to the autostereoscopic display with the highest resolution, low crosstalk, Moiré- and defect- pattern free.

Glasses-free 3D display with glasses-assisted quality: Key innovations for smart directional backlight autostereoscopy

A glasses-free 3D display with glasses-assisted quality is presented. Self-adaptive algorithm is employed to optimize system parameters, which is applied to design the micro structure of lens array and free form surface backlight units. Moiré contour map based on contrast sensitivity function is simulated and is manipulated by ameliorating the period ratio and the tilt angle of the superimposed periodical optical components. Directional transmissions of multi-users 3D images are realized with a finer dynamic synchronized backlight control and a face recognition technology. Comfortable viewings are demonstrated for two viewers, with full high definition for a single viewing channel. Minimum crosstalk as low as 2.3% is demonstrated over a large viewing volume.