Posted on 11/27/2024 6:42:48 AM PST by Red Badger
A new composite material developed by KIMS researchers absorbs over 99% of electromagnetic waves from different frequencies, improving the performance of devices like smartphones and wearables.
A team of scientists from the Korea Institute of Materials Science (KIMS) has developed the world’s first ultra-thin film composite material capable of absorbing over 99% of electromagnetic waves from various frequency bands, including 5G/6G, WiFi, and autonomous driving radar, using a single material.
This novel electromagnetic wave absorption and shielding material is less than 0.5mm thick and is characterized by its low reflectance of less than 1% and high absorbance of over 99% across three different frequency bands.
Conceptual Diagram of New Electromagnetic Wave Absorption and Shielding Material A conceptual diagram of the electromagnetic wave absorption and shielding material developed by the research team, along with the designed conductive pattern. Credit: Korea Institute of Materials Science (KIMS)
Challenges in Electromagnetic Wave Absorption
Electromagnetic waves emitted by electronic components can cause interference, leading to performance degradation in nearby electronic devices. Electromagnetic shielding materials are used to prevent this, and absorbing electromagnetic waves is more effective at reducing interference than merely reflecting them. However, conventional electromagnetic shielding materials reflect over 90% of the waves, with an actual absorbance often as low as 10%. Moreover, materials with higher absorbance are typically limited to absorbing electromagnetic waves within a single frequency band.
Advancements in Multi-Frequency Absorption
To overcome these limitations, the research team developed a composite material that can absorb electromagnetic waves across multiple frequency bands simultaneously. This technology absorbs and eliminates electromagnetic waves, resolving secondary interference issues. The material is also thin, flexible, and durable enough to maintain its shape even after being folded and unfolded thousands of times, making it suitable for rollable phones and wearable devices.
KIMS New Electromagnetic Wave Absorption and Shielding Material
The electromagnetic wave absorption and shielding material developed by the research team, showing its thin and flexible form & its shape remaining intact even after 5,000 bending tests. Credit: Korea Institute of Materials Science (KIMS)
Enhancements in Material Technology and Applications
The team, led by Dr. Byeongjin Park and Dr. Sang Bok Lee from the Composites & Convergence Materials Research Division at KIMS, synthesized a magnetic material by altering the crystal structure of ferrite, enabling it to selectively absorb desired frequencies. They produced an ultra-thin polymer composite film and incorporated conductive patterns on the film’s back side to control the propagation of electromagnetic waves. By adjusting the shape of the conductive pattern, electromagnetic wave reflection at specific frequencies can be dramatically reduced. A carbon nanotube thin film with high shielding properties was also applied to the back to further enhance the material’s electromagnetic wave shielding capabilities.
Senior Researcher Byeongjin Park of KIMS, who led the project, commented, “As the applications of 5G/6G communications continue to expand, the importance of electromagnetic wave absorption and shielding materials is growing.” He added, “This material has the potential to significantly improve the reliability of wireless communication devices such as smartphones and autonomous vehicle radars.”
Reference: “Absorption-Dominant Electromagnetic Interference (EMI) Shielding across Multiple mmWave Bands Using Conductive Patterned Magnetic Composite and Double-Walled Carbon Nanotube Film” by Byeongjin Park, Sosan Hwang, Horim Lee, Yeonsu Jung, Taehoon Kim, Suk Jin Kwon, Dawoon Jung and Sang-bok Lee, 28 May 2024, Advanced Functional Materials. DOI: 10.1002/adfm.202406197
This research was funded by KIMS’ fundamental research projects and the Electromagnetic Solution Integrated Research Group (SEIF) under the National Research Council of Science & Technology. The findings were published as the cover article in the October 1st edition of the internationally renowned journal Advanced Functional Materials (first author: Dr. Byeongjin Park). The research team has completed domestic patent registration and has also applied for patents in the U.S., China, and other countries. Additionally, the technology has been transferred to several domestic material companies, and it is currently being applied to actual communication devices and automobiles.
That’s what the blue roof is for.
Couldn’t you just infer where an item was from where you didn’t receive a return signal? I don’t know if it is the same principle, but that F117 that was shot down was tracked with repurposed cell phone tower technology.
Good. Saved ME from having to be pedantic.
You have rolls of it in your kitchen pantry.
Its not terribly impressive, how you know that they know is that they use percentages instead of the standard logarithmic representation in decibels, which is typical for discussing shielding applications.
What else? Polymer-carbon foam, silvered mylar, many other things that can be engineered to be frequency selective surfaces.
Do you have any more questions?
Can we make hats with it?
My tin foil one isn’t as effective as it use to be.
The word for this phenomenon in the visible spectrum is called ‘black’.
Sure but then your home Wi-Fi won't work.
However, there is always a however, you would have to have either no windows or line them with a transparent form of this stuff.
“You have rolls of it in your kitchen pantry.”
Not even close!
Either you are not a RFEngineer or you have a read8jg comprehension problem.
Aluminum foil absorbs almost non of the referenced signals.
Attenuation is about 3db compared to 20db.
I would assume that it polarizes it even more, like a battery.
But we all know what happens when we ass-ume.
"So.. is this capable of making planes, tanks, missiles and people electronically invisible?
But tin foil is shiny and adds some bling.
And gamma rays would probably zip right through...
Only if I try to use it from the backyard.
Good grief. Did I hurt your feelings?
Try again.
The shape and edges of certain lengths are still a problem.
Can you make it into a hat?
So,it’s an invisibility film?🤔
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