Research And Implementation On Key Technologies Of Solid-state 3D Volumetric Display

Volumetric display is one of the main technologies to achieve true three-dimensional display,and the static volumetric display is characteristic of no moving parts,which has a very high development potential.In this dissertation,the visual mechanism and imaging mechanism of the true three-dimensional display are expounded,and the high speed real-time processing method of massive display data and its FPGA implementation are deeply studied.The true 3D imaging quality improvement and optimization methods are proposed,including depth anti-aliasing algorithm based on classified mapping,gray-scale correction method and optimization and evaluation method of flicker.Finally,the research and development of the true 3D display prototype are completed.The main contributions of the dissertation are as follows:1)Visual mechanism and imaging analysis of true 3D display.The vision persistence,apparent movement phenomenon and spatial and temporal resolution of human sight,which form the basis of volumetric display,are discussed.Voxel,display space and the principle and characteristics of true three-dimensional imaging are expounded,and the concept of "volumetric column" is proposed.The data flow of the true three-dimensional display is studied by using Plenoptic function.The study of the related visual mechanism and the basis of imaging provides a theoretical basis for the research and design of true 3D display system.2)Research and implementation of high-speed real-time processing method for massive display data.The processing flow of true 3D display data is analyzed,and the generation,encoding and transmission methods of true 3D volumetric data are presented.The image preprocessing method and the design goal and function description of the image engine are expounded.Various data conversion and address mapping methods in image engine processing are studied in depth,and related mathematical models are established.On the basis of theoretical research,a FPGA implementation method of the true 3D image engine is proposed,which can realize the high-speed and real-time processing of massive display data.3)Research on the method of improving the quality of true 3D imaging.In view of the display defects caused by structure and photoelectric characteristics of the display body,a series of display quality improvement methods are put forward.Aiming at the problem of depth discontinuity,a true 3D depth antialiasing algorithm based on classified mapping is proposed.The concept of inter layer gradient is proposed,and the influence of different mapping types on depth continuity is analyzed.Besides,an algorithm for determining the type of voxel mapping is given.In order to deal with the problem of gray-scale distortion,the imaging luminance variation function and gray-scale deviation are derived by analyzing the photoelectric characteristics of the display volume.By adjusting the driving sequence of the display volume and the sub-frame length,combined with gamma correction,the gray-scale correction is realized and the display contrast is improved.In order to evaluate flicker degree of true 3D display,a method of temporal contrast sensitivity function weighted amplitude contrast and a display volume refreshing method of inter-layer scanning are proposed,and two groups of visual perception experiment are completed.By means of the correlation analysis between the objective quantification results of the evaluation model and the scoring results of the subjective experiments,the accuracy of the evaluation model and the validity of the refreshing method are verified.4)Development and implementation of a prototype of true 3D system.The overall architecture of true 3D display system is proposed,and design and assembly of subsystems such as display data processing circuit,projection light path and display volume and its driving are discussed.The data receiving of DLP circuit and DMD reset timing design,the light path structure and light source design and the display volume photoelectric characteristics and driving method design are expounded.The main performance parameters of the system are tested and evaluated,and the three-dimensional imaging experiments are carried out.The results show that the overall performance of the prototype developed in this dissertation can reach the international advanced level.The performance of the prototype of true 3D display system developed in this dissertation achieves the desired design goals.In the process of development,the key technologies of independent intellectual property rights has been mastered.The set up of this prototype accumulates experience and provides an important physical verification platform for future theoretical research and engineering practice of volumetric true 3D display technology.