2020 IEEE 20th International Conference on Software Quality, Reliability and Security Companion (QRS-C) Development of A Real 3D Display System Chong Zeng Weihua Li Hualong Guo College of Mathematics and College of Mathematics and College of Mathematics and information Engineering information Engineering information Engineering Longyan University Longyan University Longyan University Longyan, China Longyan, China Longyan, China Tung-lung Wu School of Mechanical and Automotive Engineering Dennis Bumsoo Kim Zhaoqing University College of Mathematics and information Engineering Zhaoqing, China Longyan University Longyan, China Abstract—This paper introduces a three-dimensional light achieve high fidelity of the reproduced objects by recording field display system, which is composed of a high-speed total object information on the phase, the amplitude, and the projector, a directional scattering mirror, a circular stainless- intensity at each point in the light wave [4]. steel bearing plate, a rotating shaft and a high-speed micro motor. The system reduces information redundancy and Recently, Cambridge Enterprise invented a novel 360e computational complexity by reconstructing the light intensity 3D light-field capturing and display system which can have distribution of the observed object, thus generating a real three- applications in gaming experiences, an enhanced reality and dimensional suspended image. The experimental results show autonomous vehicle infotainment and so on [5]. Motohiro et that the suspension three-dimensional image can be generated al. presented an interactive 360-degree tabletop display system by properly adjusting the projection rate of the image and the for collaborative works around a round table so that users rotation speed of the rotating mirror (i.e. the motor speed). The could see 3D objects on the tabletop display anywhere around clarity and accuracy of a three-dimension display depending on the table without 3D glasses [6]. Nonetheless, there are some the number of slices selected, meaning that the more slices can disadvantages which are huge amount of the information, be projected per minute, the finer the three-dimension display. redundancy of holographic images, and a limit of visibility at Finally, this study provides the basic parameter matching, certain angles. Thus, it is needed to develop a new real 3D which shows the feasibility of developing a real light field 3D display which overcomes such problems and reconstructs 3D display system with stable performance, strong portability, easy implementation, and low cost. In short, naked-eye 3D allows the images with the appropriate light filed distribution to show the observer to view objects from any angle and direction, without object images in every direction. This study purposes to the need for any auxiliary tools (such as glasses, helmets, etc.). suggest a prototype real 3D display based on principles of the persistence of vision and a light field with CMOS Keywords— real 3D, DLP, DMD, high-speed projector, light (complementary metal̢oxide̢semiconductor) image field display sensors, Infrared sensors and DLP (digital light processing). The system expects to project images through a single high- I. INTRODUCTION speed projector, with the light filed distribution in every In stereoscopic vision, the eye can capture two different direction of the object. The new real 3D display is expected to views of a 3D object, and the retinal image is merged in the apply for many fields of industries for education, medical, observer's brain to produce a three-dimensional image of the manufacturing and so forth. object, by converting parallax to depth perception. The distance determination is possible through the stereopsis II. RELATED WORK usually with binocular depth perception owing to the Since Levoy et al. created light fields through large-scale horizontal separation and disparity of two eyes [1]. The 3D rendering and digital image arrays to generate views that can display is visually persistent, in which light stays in the eye for be viewed from any angle within a certain range, light fields a short time after it stops entering, leading to optical illusions. have become one of the important tools in computational Geng defined a perfect 3D display to be a “window to the photography [7]–[9]. Zwicker et al. proposed a method to world” through which viewers can perceive the same 3D scene record the light fields include camera aperture, the number of as the viewers see the real object. Although many of enhanced views rendered around the circle, the amount of horizontal 3D images have depth or volume, a flat screen can only show diffusion [10]. There are many displays based on light fields, still only 2D images due to the nature of the 2D display [2]. such as near field display [11], compressed light field display Beigzadeh noted that the primary real (perfect) 3D display [12]–[14], and glasses-free light field displays [15]. In technology involved interference and diffraction to record and particular, the emergence of autostereoscopic display reconstruct a real 3D object like holography which can achieve technology based on light field display makes 3D display high fidelity of the reproduced object by recording total object develop significantly. The earliest autostereoscopic display information of the phase, amplitude, and intensity at each adopting three high-speed DLP projectors as display point in the light wave [3]. The primary real 3D display components were with an observable 3D field of view of only technology considers interference and a diffraction to record 180 degrees [8]. Then Andrew et al. introduced a set of and reconstruct 3D objects like a holography which can rendering technology for interactive horizontal parallax light 978-1-7281-8915-4/20/$31.00 ©2020 IEEE 644 DOI 10.1109/QRS-C51114.2020.00109 field display systems, in which only a high-speed DLP degrees, and the scattering rate in the Y direction was projection, a rotating mirror, and FPGA circuit and so on to more than 100 degrees. present 360-degree three-dimensional surround display [4]. Since then, various autostereoscopic display technology based The carrying plate is made of solid stainless steel for on light field display has been emerging ongoing. For fixing the diffuser and the rotating shaft is connected example, a digital projector array and a micro-lens enhanced to the micromotor. Considering the huge eccentricity projection screen are used to simulate the light field of a given generated by high-speed rotation, it is necessary to 3D scene to form an automatic stereo display [16]; Douglas et accurately calculate the load bearing and center of al. illustrates a dynamic light field display adopting multi- gravity. layered LCDs [17]; Xia et al. created the light field of real 3D The system requires a proportional reducer to reduce scene floating in the air, using high-frame-rate color projector eccentricity, improve power control, and improve and flat light field scanning screen [18]; A 360-degree light equipment stability. The speed of the micromotor field 3D display system is proposed, which consists of a liquid needs to be adjusted between 1000-1500 rpm to reach crystal display, a new triplex lens array, and a holographic the rotating frequency of the diffuse reflector. functional screen . III. SURROUND LIGHT FIELD DISPLAY SYSTEM 濼瀀濴濺濸澳 濛濼濺濻激瀆瀃濸濸濷澳 A. Principles and Main Components of the System 瀃瀅瀂濽濸濶瀇瀂瀅澳 1) Persistence of vision: This makes a reference to the optical illusion that occurs when visual proceeding from it has ceased to enter the eye [19]. 2) Light field: The surround 3D display reconstructs the 濗濼瀅濸濶瀇濼瀂瀁濴濿澳 light field of all light rays in 3D objects from and through 濦濶濴瀇瀇濸瀅濼瀁濺澳 every direction and point. The light rays are captured using 濠濼瀅瀅瀂瀅澳 the 5D (five dimensional) plenoptic function in three 澳 coordinate axis and two angles to specify the directions of 3D objects. Removing any redundant information form the five- dimensional plenoptic function makes it easy to record the 濖濴瀅瀅瀌濼瀁濺澳 light field. A traditional digital camera only captures 2D 濗濼瀆濶澳 images and its image sensor records colors and brightness of 濥瀂瀇濴瀇濼瀁濺澳 all light rays in every individual pixel. However, a light field 濦濻濴濹瀇澳 camera records not only the brightness and colors, but also 濠濼濶瀅瀂澳濠瀂瀇瀂瀅澳 directions of all the light rays reaching to its sensor. Then, the 瀅 camera refocuses the images [20]. 3) Digital Light Processing (DLP): The high-speed projector (DLP) is used to project the preprocessed image (a Fig. 1. The model of Surround 3D Display light field image) onto the high-speed rotating scattering mirror. A DLP is a set of chipsets that use a DMD (digital micromirror device) [4]. B. Eq The Model of the Surround 3D Display System Figure 1 shows the imaging structure of the 3D display system, which is consisted of a high-speed projector, a directional scattering mirror, a circular stainless steel carrying 澳 disk, a rotating shaft, and a micro electric motor. 3D Max was used to model the observed object and 瀂澳 sliced the image. High - speed projector adopts DMD - based DLP with 瀌澳 circuit module. It has high - speed graphic sequence storage and display function, and is equipped with high - performance, high - resolution spatial light modulator. The projected graphic sequence ranges from 150hz /s to 200hz /s to match the rotation speed of the scattering mirror. The DSM (directional scattering mirror) is placed on the bearing plate at a 45-degree angle to the horizontal plane. As shown in Fig. 2, its center of gravity should Fig. 2. The Diagram of DSM be the center of gravity of the disk to ensure stability. Meantime, the mirror surface is optically coated by using the Light Shaping Diffusers (LSD), so that the scattering rate in the X direction was less than 2 645 C. The principle of the real 3D Display B. Prevention of Vibration As shown in Fig. 2, DLP is projected onto the DSM surface It is very important to stabilize the equipment without and light is scattered to the surrounding environment at a fixed vibration for better images.