Phase-Shifting Structured Illumination with a Polarization-Encoded Metasurface.

Area of Science:

• Optics and Photonics
• Metrology
• Materials Science

Background:

• Phase-shifting structured illumination is crucial for advanced imaging techniques like 3D surface measurement.
• Conventional methods often involve complex, bulky mechanical or optoelectronic systems, hindering practical applications.
• There is a need for compact, stable, and integrated solutions for generating structured light patterns.

Purpose of the Study:

• To introduce a novel polarization-controlled dielectric metasurface for generating phase-shifting fringe patterns.
• To demonstrate a compact and robust structured light projection system.
• To enable efficient 3D surface measurement using the developed metasurface.

Main Methods:

• Design and fabrication of a polarization-controlled dielectric metasurface.
• Encoding distinct phase gratings for orthogonal polarizations to create lateral fringe displacements.
• Experimental demonstration of fringe generation and application in fringe projection profilometry for 3D surface measurement.

Main Results:

• Successful generation of high-quality phase-shifting fringe patterns in the visible spectrum.
• Demonstration of a compact, millimeter-scale metasurface device.
• Accurate 3D surface measurement of objects using the metasurface-based structured illumination system.

Conclusions:

• The polarization-controlled dielectric metasurface provides a compact, passive, and robust solution for structured light generation.
• This technology integrates multiple phase-shifting steps into a single static device.
• The approach has broad potential for optical metrology, computational imaging, and other applications requiring structured illumination.