4D surface shape measurement system with high spectral resolution and great depth accuracy

Area of Science:

• Optics and Photonics
• Metrology
• Computer Vision

Background:

• Accurate 3D surface characterization is crucial for many scientific and industrial applications.
• Integrating spectral information with 3D morphology offers enhanced material and surface analysis capabilities.
• Existing systems often lack the combined resolution and accuracy for comprehensive 4D surface analysis.

Purpose of the Study:

• To develop and validate a 4D surface shape measurement system combining spectral detection and 3D surface morphology.
• To achieve high spectral resolution and great depth accuracy (HSDA) in a single integrated system.
• To demonstrate the system's versatility across diverse application domains.

Main Methods:

• A hyperspectral imager using a grating for precise spectral data acquisition.
• A structured light stereovision system for 3D point cloud reconstruction.
• A double light path module for precise coupling and point-to-point correspondence between spectral and 3D data.
• Fusion and transformation of spectral and 3D coordinate data into a 4D dataset.

Main Results:

• The developed HSDA system achieved a spectral resolution of 3 nm and a depth accuracy of 27.5 μm.
• Successful 4D imaging experiments demonstrated the system's capabilities.
• The system effectively fused spectral and 3D morphological data into a comprehensive 4D dataset.

Conclusions:

• The proposed HSDA system successfully integrates high spectral resolution and great depth accuracy for 4D surface measurements.
• The system's versatile performance was validated through various experiments.
• Potential applications include fluorescence detection, face anti-spoofing, health assessment, and plant monitoring.