在技术变革和资本力量的双重推动下，虚拟现实（virtual reality）技术在近几年发展迅速，初步达到了可商业化的程度。虚拟现实和3D 电影院都是通过双目视差实现三维成像，但虚拟现实提供了3D 电影院所不具备的移动视差并提供了强烈的沉浸感。现阶段虚拟现实技术仍面临着一系列技术难题，其中眩晕和人眼疲劳尤其明显，是虚拟现实的技术禁地。本文从介绍三维视觉感知开始，分析了虚拟现实造成眩晕和人眼疲劳的根本原因。给出了解决这一技术瓶颈的答案——动态光场，并从光场采集和显示两方面分析了多种光场技术的优缺点。列举了增强现实（augmented reality）技术的3 种实现形式，并从人与人交互和通信的角度对比了虚拟现实与增强现实在未来的发展趋势。
With the boost of both cutting-edge technologies and capital strength, the Virtual Reality(VR) makes a fast progress in recent years. And a technical maturity is reached for VR to be commercialized. With both the virtual reality and the 3D cinema, a stereoscopic display is generated based on the binocular parallax. But virtual reality provides more depth cues (e.g. the motion parallax) with a strong immersion than the 3D cinema. The current generation of the virtual reality still faces a series of technical problems. Especially, the vertigo and the eye fatigue are the toughest problems impeding the long-term applications of the VR. This paper briefly discusses the 3D visual perception and the causes of the vertigo and the eye fatigue. A solution to this technological bottleneck is suggested: the Dynamic Light Field. In addition, various light field technologies are compared related to the photograph and the display. At the end, three types of the augmented reality (AR) are presented and the commercial development trend of the AR and the VR are analyzed from perspectives of social interaction and communication.
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