Measurement technology based on a Stokes parametric polarization system

Area of Science:

• Optics and Photonics
• Computer Vision and Image Processing
• Metrology

Background:

• Structured light measurement systems commonly employ polarization filters to mitigate interference from highly reflective surfaces.
• However, conventional polarization filtering can reduce image brightness in dark areas, compromising measurement accuracy.
• Existing methods struggle with interference and suboptimal image quality in challenging lighting conditions.

Purpose of the Study:

• To propose and validate a new structured light measurement method using Stokes parameters to overcome limitations of traditional polarization filtering.
• To enhance measurement accuracy and efficiency by optimizing polarization angle selection.
• To improve overall image quality and signal-to-noise ratio in structured light systems.

Main Methods:

• A novel measurement approach utilizing Stokes parameters is proposed for polarization-based structured light systems.
• Images are captured at specific polarization filter angles (0°, 45°, 90°) to calculate Stokes parameters and generate a polarization angle histogram.
• A quantitative mathematical model determines the optimal polarization angle through orthogonal processing, followed by image fusion of preferred polarization images.

Main Results:

• The proposed method effectively reduces interference in highly reflective regions, a common issue with conventional polarization filters.
• Significant improvements in fringe pattern quality and signal-to-noise ratio were observed.
• The quantitative mathematical model enabled rapid and accurate selection of polarization angles, boosting system efficiency.

Conclusions:

• The Stokes parameter-based method offers a robust solution for structured light measurements in environments with varying reflectivity.
• This approach enhances measurement accuracy and system efficiency by optimizing polarization parameters.
• The technique successfully addresses interference and improves image quality, making it valuable for advanced metrology applications.