Single-shot 3D imaging with point cloud projection based on metadevice

Abstract

Three-dimensional (3D) imaging is a crucial information acquisition technology for light detection, autonomous vehicles, gesture recognition, machine vision, and other applications. Metasurface, as a subwavelength scale two-dimensional array, offers flexible control of optical wavefront owing to abundant design freedom. Metasurfaces are promising for use as optical devices because they have large field of view and powerful functionality. In this study, we propose a flat optical device based on a single-layer metasurface to project a coded point cloud in the Fourier space and explore a sophisticated matching algorithm to achieve 3D reconstruction, offering a complete technical roadmap for single-shot detection. We experimentally demonstrate that the depth accuracy of our system is smaller than 0.24 mm at a measurement distance of 300 mm, indicating the feasibility of the submillimetre measurement platform. Our method can pave the way for practical applications such as surface shape detection, gesture recognition, and personal authentication.

Metasurface-based computational imaging: a review

“…Wide-angle illumination for 3D depth imaging based upon: (d) pseudo-random coding, reproduced with permission from Ref. 73 (CC-BY), (e) uniform dense light patterns, reproduced with permission from Ref. 6 (CC-BY), (f) double-zone illumination, reproduced with permission from Ref.…”

High-Resolution, Wide-Field-of-View, and Real-Time 3D Imaging Based on Spatial-Temporal Speckle Projection Profilometry with a VCSEL Projector Array

“…Optical 3D measurement, as a promising metrology technique with the use of light as information carriers, , is extensively applied in intelligent manufacturing, scientific research, and medical diagnosis. With the advent of the laser and charge-coupled device (CCD), many optical metrology methods and instruments are employed in fast 3D modeling, robot navigation, microscopic 3D imaging, − and AR/VR, such as time-of-flight (TOF), − stereo vision, , and structured light projection. − TOF directly perceives the depth information on the target by recording the time difference from sending to receiving the modulated light signal, which is exclusively used for long-distance 3D sensing in driverless cars or visual navigation, but its close-range measurement accuracy and resolution are relatively low. Stereo vision captures the intensity information on the scenes from two or more cameras and establishes the corresponding relationship between different perspectives by stereo matching, − realizing passive 3D imaging based on triangulation.…”

Spatially Structured-Mode Multiplexing Holography for High-Capacity Security Encryption

“…With the rapid development of digital computers, computer-generated holography (CGH) has made many important progresses in recent years. For instance, CGH has been extended from 2D to 3D using advanced optimization algorithms. − In addition to coherent light sources, partially coherent light sources are also introduced to perform optical CGH . Importantly, holographic multiplexing technologies make it possible to encode multiple patterns into one hologram.…”