Depth plane adaptive integral imaging system using a vari-focal liquid lens array for realizing augmented reality

Augmented reality (AR) is an interactive experience of a real world environment where the objects that reside in the real world are enhanced by computer generated perceptual information. Despite its attractive features, AR has not become popular because of the visual fatigue that many people face when they experience it. Many methods have been introduced to solve this visual fatigue problem and one of these methods is an integral imaging system that provides images almost continuous viewpoints and full parallax. However, the integral imaging system, which uses a lens array with a fixed focal length, has limited depth of focus (DOF) range. As a result, images that are outside of the DOF range become degraded. In this paper, an vari-focal liquid lens array was fabricated and the optical characteristics of the lens array were evaluated and improved. Using the vari-focal liquid lens array, the DOF range was improved and high resolution images are realized without restriction of depth range in an AR system.