Principle And Establishment Of The Omnidirectional-View Three-dimensional Display

Multi-view three-dimensional (3D) display technique is one of the most popular three-dimensional displays. Nowadays, with the development of multi-view display, omni-directional three-dimensional display is presented, which is a new research direction of 3D display. It has super multi-views in horizontal direction and can display 3D images with high resolution. Compared with volumetric display, it has a good occlusion-capable effect, which is a 3D display technique in line with the human vision.In this paper, the theory of omni-directional 3D display with cylindrical image space is presented from some existing omnidirectional 3D displays. This theory indicates that the image space of all omni-directional 3D displays with only horizontal parallax is cylindrical space, the size of which is dependent on the most marginal pixel location and the maximum scanning angle. The existing omni-directional 3D displays mainly contains cylinder direction-selective type, plane parallel direction-selective type and plane converge direction-selective type. With these three kinds of 3D displays, the optical characteristic of direction-selective screens and their display principle are analyzed in detail. The study on the mapping relation between the projecting view and pixels directs the study on the image rendering algorithm and distortion correction. At the same time, the study is also helpful to understand the 3D image distribution in different depth with different spatial resolution. The virtual voxel distribution in the cylindrical space is investigated. The requirement to the number of images all round is studied from stereoscopic vision, projecting view resolution and virtual voxel spatial resolution.The color omnidirectional 3D display system based on cylindrical LED screen is discussed in detail. The display principle, image rendering, system parameter design and simulation, and circuit control design are analyzed. The key to this display principle is to control the each pixel's light emitting direction and angle. The center light direction and emitting angle in each view and the pixels'view distribution in the observed view are calculated. An image rendering method based on omni-directional views of a 3D scene is proposed. Through analysis of maximum scanning angle, rotation speed and pixels'number in one revolution, a set of reasonable system parameters is designed, which has been validated via simulation. The circuit design mainly has two technical difficulties:high-speed addressing and display synchronicity. In debugging display synchronicity, owing to the LED asymmetrical distribution and parallax barrier's pitch ununiformity, the debugging method has two steps:pixel synchronization and view synchronization. With this debugging method, color 3D display is completed successfully.With the development of 3D display, display image evaluation is gradually focused on. We have investigated the geometry, bright, color, space characteristic of display 3D image with quantitative indeces. We have designed a series of test imag es for these characteristic, and detect all characteristics in experiment.3D image evaluation can show performance of 3D display system, which can be used for comparing among different 3D display systems, but also give higher display performance-for next-generation 3D display.At last, we have discussed the development of the omnidirectional-view 3D display. The relation between view number and 3D image resolution is investigated. We obtain system parameters of omnidirectional-view 3D display with better 3D image according the LED display frequence, massive data transmission, and LED arrangement pitch, which shows us a research direction of future development.