Reconfigurable step-zoom metalens without optical and mechanical compensations

Area of Science:

• Optics and Photonics
• Metamaterials Science

Background:

• Metasurfaces enable advanced optical functions through subwavelength nanostructures.
• Polarization-dependent metasurfaces offer independent phase control for reconfigurable optics.

Purpose of the Study:

• To design and demonstrate a highly integrated step-zoom metalens with dual focal lengths.
• To achieve polarization-controlled, reconfigurable zoom capabilities with aberration correction.
• To maintain a stable image plane for practical optical systems.

Main Methods:

• Utilizing double-sided metasurfaces on a transparent substrate.
• Assigning focal power and balancing aberrations between front and rear metasurfaces.
• Employing full-wave numerical simulations to verify performance.

Main Results:

• A large field-of-view (±20°) step-zoom metalens with dual focal lengths was designed.
• Monochromatic aberrations were corrected, achieving nearly diffraction-limited image quality.
• The image plane remained constant during zoom switching.

Conclusions:

• The proposed metalens offers ultra-compactness, flexibility, and simplicity for integrated zoom imaging.
• This technology has potential in applications requiring beam focusing without optical or mechanical compensation.
• The stable image plane enhances practical utility in diverse optical systems.