Pixel-wise absolute phase unwrapping using geometric constraints of structured light system

Area of Science:

• Computer Vision
• Metrology
• Optical Engineering

Background:

• Phase unwrapping is crucial for 3D reconstruction using structured light systems.
• Traditional methods often require multiple acquisitions or additional cameras, increasing complexity and cost.
• Existing techniques can struggle with accuracy and robustness in certain scenarios.

Purpose of the Study:

• To develop a novel, single-shot absolute phase unwrapping method for structured light systems.
• To eliminate the need for additional image acquisitions or cameras in phase unwrapping.
• To achieve pixel-by-pixel absolute phase determination using only geometric constraints.

Main Methods:

• Creation of an artificial absolute phase map (Φmin) at a virtual depth plane (z = zmin).
• Generation of Φmin is based solely on the geometric constraints of a calibrated structured light system.
• Pixel-by-pixel unwrapping of the wrapped phase by referencing the generated Φmin.

Main Results:

• Successfully demonstrated a pixel-by-pixel absolute phase unwrapping method.
• The proposed method does not require additional image acquisition or cameras.
• The unwrapped phase is absolute for each pixel due to Φmin being defined in projector space.

Conclusions:

• The novel method provides accurate absolute phase unwrapping for structured light systems.
• This approach simplifies the 3D reconstruction process by reducing hardware and acquisition requirements.
• The technique offers a robust and efficient solution for phase unwrapping challenges.