Color-and-polarization encoded annular LED array for real-time active polarization imaging

Area of Science:

• Optics and Photonics
• Image Processing
• Materials Science

Background:

• Conventional polarization imaging often requires specialized cameras or complex setups.
• Existing methods can suffer from polarization errors and limited spatial resolution.
• Efficient imaging of dynamic targets with polarization information remains a challenge.

Purpose of the Study:

• To develop a real-time active polarization imaging system using readily available components.
• To enhance polarization feature retrieval and overcome limitations of current technologies.
• To demonstrate the system's capabilities for industrial inspection and biomedical applications.

Main Methods:

• Utilized a color-and-polarization-encoded annular LED array with red, green, and blue (RGB) light sources.
• Employed a standard color camera, eliminating the need for specialized polarization cameras.
• Integrated linear polarizers (0°, 45°, 90°) and implemented crosstalk correction and white balance algorithms.

Main Results:

• Achieved a twofold improvement in spatial resolution compared to commercial division-of-focal-plane (DoFP) cameras.
• Demonstrated high measurement accuracy with a maximum error of 4.7% against rotating polarizer methods.
• Reached an imaging speed of 39.34 FPS at 2448×2048 resolution using GPU acceleration.

Conclusions:

• The proposed technology offers an efficient framework for real-time polarization imaging of dynamic targets.
• The system provides superior spatial resolution and accuracy without specialized hardware.
• Significant potential for applications in industrial inspection and biomedical imaging is highlighted.