Dual-polarized angle-selective surface with ultra-narrow angular selectivity and broadband characteristics

Area of Science:

• Electromagnetics and Optics
• Materials Science

Background:

• Angle-selective surfaces (ASS) are crucial for controlling electromagnetic wave propagation based on incidence angle.
• Existing ASS designs often struggle to balance narrow angular selectivity with broadband operation and dual-polarization capabilities.

Purpose of the Study:

• To design and demonstrate a novel angle-selective surface (ASS) with ultra-narrow transmission and broadband characteristics.
• To achieve high angular selectivity for both transverse electric (TE) and transverse magnetic (TM) polarizations.

Main Methods:

• The ASS was designed using two identical layers of frequency-selective surfaces (FSS) with regular hexagonal structures.
• Equivalent circuit model (ECM) theory and modal interaction poles (MIPs) principle were employed to optimize interlayer height and electromagnetic coupling.
• A prototype was fabricated and its performance was measured and compared with simulations.

Main Results:

• The proposed ASS exhibits ultra-narrow angular domain transmission (<0.1° for TE, 0.7° for TM) and narrow transition domains.
• Broadband angular selectivity was achieved over 4.1 GHz (TE) and 5.4 GHz (TM) bandwidths.
• Measurement results closely matched simulation predictions, validating the design.

Conclusions:

• This work presents the first ASS with integrated broadband characteristics, ultra-narrow transmission, and dual-polarization support.
• The structure demonstrates superior angle-selective performance compared to existing solutions.
• Potential applications include telescope imaging, augmented reality (AR) waveguides, optical communications, and privacy protection.