Wideband optically transparent absorber based on multilayer ITO films with high absorption rate

Area of Science:

• Materials Science
• Electromagnetics
• Optics

Background:

• Traditional electromagnetic absorbers often lack optical transparency.
• The need for transparent materials in electromagnetic compatibility (EMC) is growing.

Purpose of the Study:

• To design, fabricate, and measure a wideband, optically transparent absorber.
• To achieve high absorption performance while maintaining optical transparency.

Main Methods:

• Utilized multilayer indium tin oxide (ITO) films and polyethylene terephthalate (PET) films.
• Replaced traditional dielectric substrates and metal patterns with ITO and PET.
• Investigated absorption under transverse electric (TE) and transverse magnetic (TM) polarizations and varying incident angles.

Main Results:

• Achieved absorption above 90% from 4.92 to 24.55 GHz for both TE and TM polarizations.
• Exceeded 95% absorption in the range of 5.74–21.85 GHz.
• Demonstrated outstanding stability across a wide range of incident angles.

Conclusions:

• The proposed absorber exhibits excellent optical transparency and wideband high absorption.
• The device is a promising candidate for transparent electromagnetic compatibility applications.
• Experimental verification confirmed the design's performance.