Since the early 2000s, flat-panel displays have advanced exponentially in both multi-user and personal applications. Color expression and the resolution of images provided by the state-of-the-art displays are beyond the perceptible range of human eyes and virtually indistinguishable from the real world. However, display technologies can go further to provide an immersive and realistic experience. In order to achieve those goals, a three-dimensional (3D) expression of a display is an essential factor because we live in a 3D world and perceive it as 3D information.
3D displays are beneficial compared to two-dimensional (2D) displays because the process of observing images is more similar to the natural experience than that of 2D displays. However, the technological limitation of 3D displays limits the popularity of 3D display applications. Current applications of 3D displays are mostly focused on the entertainment area such as movies and games due to the fixed viewing positions of observers or the use of viewing aids and the ease of generating 3D contents using computergraphics technologies rather than picking up 3D images from real objects. If the viewing conditions of 3D images and acquisition techniques of 3D information are developed enough, we can expect many other 3D display applications in addition to entertainment applications. A 3D video call or 3D teleconference can be good examples. Virtual reality (VR) or augmented reality (AR) can also have more effects on real-life applications with 3D displays. Moreover, a 3D visualization of scientific results in medical, biological, or other technological fields will be beneficial to academic analysis and education. 3D displays will be also helpful for industrial development. The prototyping of a product will be accelerated, and the training of employees will be done much more effectively with 3D displays. Consequently, many applications that currently use 2D displays may potentially use 3D displays instead.
For those purposes, one of the barriers that current 3D displays must overcome is glasses. Glasses-free, or autostereoscopic, displays provide perspectives of images according to the position of an observer. For providing perspectives, various optical elements are used in autostereoscopic systems. Although autostereoscopic technologies encompass various display technologies, a multi-view-based method is the current mainstream of 3D displays because of its compatibility with flat-panel displays. This book introduces various autostereoscopic technologies from the fundamental principles of the parallax barrier method to the latest multi-projection super-multi-view displays.
The beginning chapters explain the process of the observation of 3D images from a light source to an observer. In the real world, light emitted from a source is reflected or scattered at an object, collected by eyes and, perceived as an object. The observation of 3D images through a 3D display includes more steps: capturing, processing, and display. Instead of directly observing a real object, the information is captured by an imaging device and processed, then it is reconstructed by a 3D display. For those new to display technology, the overall background of 3D display technologies is introduced in Chapter 1. Chapters 2 and 3 focus on directional-view-based 3D displays, including multi-view and integral imaging displays. The practical guide to fabrication of each display system is provided for understanding of the basic principle of each display method. Chapter 4 deals with the acquisition of 3D information from computer graphics and real objects using an optical method. Later chapters cover further details of multi-view technologies and introduce recently reported advanced 3D display technologies.
Possible readers of this book range from undergraduate students to display manufacturers in the industry. Display basics and fundamentals of 3D displays can be a practical guide to those who do not have any background knowledge of display technologies. Examples of multi-view systems will help readers understand the configuration of basic 3D display systems. For readers with some previous knowledge of 3D display technologies, detailed explanations are also provided for advanced display technologies, such as the slanted lens technique and multi-projection systems. The References will be helpful for further study.
We tried our best to cover a wide range of autostereoscopic displays from its conceptual beginning to recent research. Because the technological advancements of conventional 2D displays affect the development of 3D displays, we also tried to cover the basics of 2D displays, including flat panel displays as well as projection-type displays. We believe that this book will help readers improve their comprehension of autostereoscopic displays. We hope that our book contributes to more active research on autostereoscopic 3D displays to realize a world of 3D displays in the near future.
We appreciate the effort of our supporters for the publication of this book. We thank Dr. James A. Harrington for his suggestion and support of the publication. We also thank SPIE staff Tim Lamkins, Tyler Koshakow, and, especially, Dara Burrows for their helpful advice, encouragement, and copyediting efforts. We acknowledge the support of our colleagues in the Optical Engineering and Quantum Electronics Laboratory, Seoul National University. Jae-Hyun Jung, Jiwoon Yeom, Chang-Kun Lee, Jonghyun Kim, Jinsoo Jeong, Changwon Jang, Youngmo Jeong, Jong-Young Hong, and Matheus Miranda helped us with researching a wide range of background technologies, illustrating conceptual diagrams of technologies, and the fabrication of example systems. The writing of this book is based on our long-term study. We especially acknowledge recent support by the IT R&D program of MSIP/KEIT (fundamental technology development for digital holographic contents) and The Cross-Ministry Giga KOREA Project (Development of Super Multi-View (SMV) Display Providing Real-Time Interaction) of The Ministry of Science, ICT and Future Planning, Korea.
Byoungho Lee
Soon-gi Park
Keehoon Hong
Jisoo Hong
December 2015