Light Field Augmented Reality Head-mounted Displays with Liquid Crystal Microlens Array

• Main Authors: Chen, Yu-Ting, 陳昱廷
• Other Authors: Huang, Yi-Pai
• Format: Others
• Language: en_US
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/q2u66f

碩士 === 國立交通大學 === 光電工程研究所 === 107 === As the development of the technology, the requirements of the display are increasing such as the higher resolution or purer color display. Take stereoscopy for example, in 2009, a movie called Avatar reached a box office record that was difficult to break in history, and its success relied on its breakthrough in 3D movies. Since then, people have invested in the development of stereoscopic display, and the technology of virtual reality (VR) and augmented reality AR come out. AR and VR can make the observer feel the virtual scenes really exist. In addition, AR and VR can not only be used in entertainment, but also be used in many industries such as manufacture, military, education, and medicine. Take AR for example, some AR head-mounted displays (HMDs) are produced by multinationals, like Google Glass or Hololens form Microsoft. However, there still have some issues need to be overcome. Traditional 3D displays generate 3D images by binocular disparity, and these 3D images can have a great depth effect. But, the observer will feel uncomfortable and have visual fatigue due to the mismatch between accommodation and convergence (A.C. conflict). Generally, current AR HMD products need another optical component to guide the panel light to the observer. Therefore, these AR HMDs cannot reach a high field of view (FOV), because of the low using efficiency of the light, and some geometric limitations. The good thing is that some researches about light field technology were proposed. The light field technology can record the intensity and angular information of the light. In addition, we can emit the recorded image and be deflected by the microlens array to reconstruct the light field image. The advantages of the light filed system are that it can provide a monocular focus cue, and the structure can remain compact and lightweight. In our research, a light field HMD structure is proposed. This structure can use twisted nematic (TN) cell and polarizers to control the polarization of incident light and displays the background image and light field image respectively. Then, using the time-multiplexing method by fast switching the voltage on the TN cell to get the AR image. Moreover, because the current transparent high-resolution panel is not mature, we have also proposed an architecture and software simulation to verify the feasibility of the original proposed light field near-eye display.