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High-resolution, High-speed, Three-dimensional Video Imaging with Digital Fringe Projection Techniques
Published on: December 3, 2013
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Phase retrieval for dual-projection pattern based on orthogonal frequency encoding to suppress superposing effects.
Applied Optics
|December 1, 2023
Summary
This study introduces orthogonal grating encoding to accurately retrieve phases from superposed grating patterns in dual-projection systems. This novel method overcomes blur and overexposure for precise 3D reconstruction.
Area of Science:
- Optical Metrology
- 3D Reconstruction
- Computer Vision
Background:
- Structured-light systems project patterns for 3D measurement.
- Simultaneous projection in dual-systems causes interference, blur, and overexposure.
- Phase miscalculation hinders accurate 3D reconstruction.
Purpose of the Study:
- To develop a novel method for accurate phase retrieval from superposed grating patterns.
- To address challenges of interference-like blur and brightness overexposure in dual-projection systems.
- To enable high-precision 3D reconstruction from simultaneous multiprojection.
Main Methods:
- Utilized orthogonal grating encoding for signal separation.
- Determined pattern frequency based on wireless communication signal separation principles.
- Applied discrete Fourier transform to superposed grating patterns for phase retrieval.
- Reconstructed 3D objects by fusing point clouds from dual-projection.
Main Results:
- Successfully eliminated interference-like blurring and brightness overexposure.
- Achieved high-precision phase maps from superposed grating patterns.
- Demonstrated accurate 3D reconstruction of measured objects.
- Validated the effectiveness of orthogonal grating encoding for simultaneous projection.
Conclusions:
- Orthogonal grating encoding is a viable method for accurate phase retrieval in dual-projection structured-light systems.
- The proposed technique overcomes limitations of simultaneous pattern projection.
- This advancement facilitates high-precision 3D reconstruction and opens possibilities for multiprojection systems.
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