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This paper presents an absolute phase unwrapping method for high-speed three-dimensional (3D) shape measurement. This method uses three phase-shifted patterns and one binary random pattern on a single-camera, single-projector structured light system. We calculate the wrapped phase from phase-shifted images and determine the coarse correspondence through the digital image correlation (DIC) between the captured binary random pattern of the object and the pre-captured binary random pattern of a flat surface. We then developed a computational framework to determine fringe order number pixel by pixel using the coarse correspondence information. Since only one additional pattern is used, the proposed method can be used for high-speed 3D shape measurement. Experimental results successfully demonstrated that the proposed method can achieve high-speed and high-quality measurement of complex scenes.
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Influence of projector pixel shape on ultrahigh-resolution 3D shape measurement
The state-of-art three-dimensional (3D) shape measurement with digital fringe projection (DFP) techniques assume that the influence of projector pixel shape is negligible. However, our research reveals that when the camera pixel size is much smaller than the projector pixel size in object space (e.g., 1/5), the shape of projector pixel can play a critical role on ultimate measurement quality. This paper evaluates the performance of two shapes of projector pixels: rectangular and diamond shaped. Both simulation and experimental results demonstrated that when the camera pixel size is significantly smaller than the projector pixel size, it is advantageous for ultrahigh resolution 3D shape measurement system to use a projector with rectangular-shaped pixels than a projector with diamond-shaped pixels.
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- PAR ID:
- 10140057
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 28
- Issue:
- 7
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 9510
- Size(s):
- Article No. 9510
- Sponsoring Org:
- National Science Foundation
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