Structured light fields 3d imaging with temporal phase unwrapping

Abstract

The passive depth map recovery based on light field data always suffers from low accuracy and high computational burden due to the noise in sub-aperture images and the narrow disparity between sub-aperture views. To overcome this problem, in this paper, temporal digital fringe projections are used to guide the accurate depth map recovery with light field camera. Since the temporal structured light field casts a set of high signal-to-noise-ratio projections onto the object, the depth map of sub-aperture image can be recovered pixel-by-pixel independently. Therefore, the accuracy of the depth map recovery could be significantly improved. In our propose method, the sub-aperture images with temporal fringe projections are extracted from structured light field information, wrapped phase maps of sub-aperture images are obtained from phaseshifting fringe analysis, the absolute phase map and depth map are recovered from a group of wrapped phase maps with temporal phase unwrapping. In our experiment, when the distance between the light field camera and reference plane is 36 cm, the measurement error of the proposed method is within 0.2 mm. The experimental results validate the effectiveness of the proposed method.