Highly Compact and Robust 3D Imaging and Shape Measurement System

The fringe projection profilometry (FPP) is one of the most widely used techniques for three-dimensional (3D) imaging and 3D shape measurements. In this paper, a FPP-based compact, portable, easy-to-implement yet robust 3D imaging and shape measurement system is explored and established. The system utilizes a series of advanced electronic devices, such as a single board computer, a credit-card sized projector, and a USB camera. It employs a number of novel techniques including ultrafast phase unwrapping with multi-frequency fringes, effective gamma correction of digital projection, arbitrary setup of system components, automatic system calibration with a least-squares inverse approach, and multi-thread parallel processing for 3D shape acquisition, reconstruction and display. The system not only provides full-field 3D information with high accuracy and fast speed, but also possesses remarkable features including but not limited to high compactness, easy implementation, and superior capability of dealing with multiple objects with complex shapes in a wide measurement range.