Telecentric Capturing System for Acquiring Light Ray Data of 3-D Objects

Abstract

In the field of computer graphics and 3-D visual communication, ray-based representation of 3-D scenes/objects has been studied. The most popular way to acquire light ray data is to take perspective projection images from multiple viewpoints, however, light rays are equivalent to orthogonal projections. This difference in projection causes errors in images synthesized from light rays. To solve this problem, we have developed a capturing system using telecentric optics, which provides orthogonal projections of objects. This system captures light rays with an angular resolution of 0.09° by rotating object (s) and taking orthogonal projection images automatically. In this paper, we discuss the implementation of the telecentric capturing system. In particular, we focus on the errors caused by disarrangement of the system's components or lens distortion, and show some methods for measuring and correcting errors. Furthermore, experimental results show the applicability of the system for acquiring light ray data as orthogonal projections and synthesizing arbitrary views.