Transparent ITO Microwave Absorber for Wideband Stealth Glazing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional microwave absorbers are optically opaque, limiting their application in scenarios requiring both microwave absorption and optical transparency, such as aircraft cabin windows and warship aperture glass, due to limited absorption bandwidth, insufficient optical transparency, complex fabrication processes, or thickness constraints.
Innovation Solution
A transparent wideband microwave absorber with a layered structure of glass substrates and specific indium tin oxide (ITO) patterns, including a square loop, cross-shaped dipole, and circular patches, achieving impedance matching across a broad frequency range.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional microwave absorber materials are used, then microwave absorption is achieved, but optical transparency is insufficient
Solution Approach 1:
The patent uses composite materials combining transparent conductive oxide (TCO) layers with dielectric layers to achieve both microwave absorption and optical transparency. The TCO-dielectric composite structure enables electromagnetic wave absorption while maintaining visible light transmission, resolving the contradiction between absorption performance and optical clarity.
Solution Approach 2:
The patent optimizes parameters including TCO layer thickness (50-200 nm), dielectric constant, and layer configuration to achieve impedance matching across microwave frequencies while preserving optical transparency. By adjusting these parameters, the absorber achieves -10 to -15 dB reflection coefficient across 3.48-13.02 GHz while maintaining >50% optical transmission.
2Ease of manufacture
If single-layer transparent absorber structures are used, then fabrication is simple, but absorption bandwidth is limited
Solution Approach 1:
The patent divides the absorber into multiple functional layers including TCO layers, dielectric layers, and patterned structures. This segmentation allows each layer to contribute differently to the overall absorption mechanism, enabling wideband performance through coordinated resonance and impedance matching across multiple frequency ranges.
Solution Approach 2:
The patent transitions from single-layer to multi-layer结构设计, adding the dimension of layer stacking to achieve wideband absorption. The multi-layer configuration creates multiple resonance modes and impedance matching interfaces that collectively broaden the absorption bandwidth from 3.48 to 13.02 GHz.
3Loss of energy
If thick absorber structures are used, then absorption performance is improved, but profile thickness increases
Solution Approach 1:
The patent employs thin-film TCO layers (50-200 nm) and thin dielectric layers to achieve effective microwave absorption with minimal thickness. The thin-film multilayer structure creates multiple reflection and absorption interfaces within a compact profile, achieving -10 to -15 dB reflection coefficient while maintaining low-profile construction suitable for stealth applications.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The absorber provides high microwave absorption and optical transparency with a low-profile design, maintaining a reflection coefficient of -10 to -15 dB across 3.48 GHz to 13.02 GHz, achieving a fractional bandwidth of 115.64% and suitable for stealth technology applications.
Implementation Method 1
These materials transform electromagnetic energy into heat while also allowing optical radiation to pass through
Implementation Method 2
allowing optical radiation to pass through
Data Source
AI summary
A transparent wideband microwave absorber unit cell, a transparent wideband microwave absorber and a method of forming a transparent wideband microwave absorber, include a metal substrate, a first layer of glass attached to the metal substrate and having a first pattern of indium tin oxide (ITO) configured as a square loop centered about a central vertical axis and a second pattern of ITO including four equidistant square patches, a second layer of glass attached to the first layer of glass and having a third pattern of ITO configured as a dipole having a cross shape with a center axis coaxial with the central vertical axis, and a third layer of glass attached to the second layer of glass and having a fourth pattern of ITO configured as five circular patches, with a first circular patch located coaxially with the central vertical axis and four equidistant circular patches.