Multi-view fringe projection profilometry for surfaces with intricate structures and high dynamic range.

Area of Science:

• Optical Metrology
• 3D Measurement Technologies
• Quality Control Systems

Background:

• Fringe projection profilometry is crucial for production line quality control.
• Challenges exist in measuring intricate structures and high dynamic range surfaces.
• Existing methods struggle with shadowing, occlusion, and specular reflections.

Purpose of the Study:

• To develop a multi-view fringe projection profilometry system to address measurement limitations.
• To enable accurate 3D measurement of complex and high dynamic range objects.
• To improve quality control in precision manufacturing and semiconductor packaging.

Main Methods:

• A multi-view system with a vertical telecentric projector and four oblique tilt-shift cameras was designed.
• A flexible calibration method using a corrected pinhole imaging model for telecentric projection was developed.
• Unified system calibration was achieved through bundle adjustment.

Main Results:

• The system achieved a 3D repeated measurement error and standard deviation of no more than 10 μm.
• Measurements were accurate within a volume of 70 × 40 × 20 mm³.
• Complete and accurate 3D measurements of high dynamic range surfaces with complex structures were demonstrated.

Conclusions:

• The developed multi-view fringe projection profilometry system effectively overcomes limitations of traditional methods.
• The system provides high accuracy and completeness for 3D measurements of challenging surfaces.
• This technology enhances quality control capabilities in precision manufacturing and semiconductor packaging.