Photonic Spin-Multiplexing Metasurface for Switchable Spiral Phase Contrast Imaging

Area of Science:

• Optics and Photonics
• Metasurface Technology
• Biomedical Imaging

Background:

• Bright-field and phase contrast imaging offer complementary morphological information.
• Miniature, cost-effective systems for switching between these modes are highly desirable for biomedical applications.

Purpose of the Study:

• To develop a compact, switchable optical imaging system using metasurface technology.
• To achieve both bright-field and phase contrast imaging capabilities within a single, ultrathin device.

Main Methods:

• Utilized a Fourier transform setup with an all-dielectric metasurface.
• Engineered the metasurface to perform 2D spatial differentiation for edge detection.
• Leveraged spin-dependent phase profiles for mode switching.

Main Results:

• Demonstrated isotropic edge detection via spatial differentiation.
• Achieved diffraction-limited bright-field imaging.
• Enabled edge-enhanced phase contrast imaging based on light's spin-state.

Conclusions:

• The proposed metasurface enables a versatile, compact optical imaging system.
• This approach integrates bright-field and phase contrast imaging, enhancing morphological analysis.
• The planar and ultrathin nature of metasurfaces offers significant advantages for future imaging and microscopy.