Time‐resolved coded structured light for 3D measurement

Abstract

Corresponding points matching is the fundamental computational task underlying stereo vision, and the key issue in making stereo vision practical is to find the most suitable algorithm to quickly match corresponding points, which leads to 3D reconstruction. In this paper, we proposed a new encoding strategy of dot-pattern structured light based on temporal modulated vertical cavity surface emitting laser (VCSEL) array, which is especially suitable for the dot projector in miniaturized devices for stereo vision. Although VCSEL has been used in Apple's iPhone X for dot projector, the time dimension information is not used. VCSEL array has the capability of controlling each light source separately, so we can encode the information of time dimension into the structured light, which improves the stereo-matching accuracy and simplifies the algorithm. In addition, compared to the temporal random speckle structured light method, this time-resolved coded dot-pattern structured light method greatly reduces the number of frames of projecting images required, which has great significance for real-time 3D reconstruction in practical applications. Therefore, the method proposed here could be of high interest for its potentials in 3D measurement in mobile phones and other miniaturized devices. The proof-of-principle experiment results verify the computational efficiency and matching accuracy of the method.

A 3D Reconstruction Method Based on Homogeneous De Bruijn-Encoded Structured Light

“…Cluster analysis divides an unknown sample set into multiple categories based on high internal similarity and low inter-class similarity. The FCM algorithm is particularly suitable for color classification due to its simplicity and fast computation capabilities [18,19]. The objective function for clustering is:…”

“…Refs. [17,18] use the K-means algorithm for color classification of colored encoding stripes, fitting straight lines for each projected color in the color space and selecting the color space origin (0,0,0) as the common point for all lines. However, experimental results show that not all point clusters can satisfy this condition, leading to errors in color classification.…”