We may not be able to fly like the superheroes of Krypton, but perhaps in the future we will have their vision on the back of our phones. At least that’s what a researcher at the University of Texas at Dallas is trying to make a reality.

Kenneth O, a professor of electrical engineering at UT Dallas, is involved in research to develop a “Superman” imaging chip that would allow users to see through materials such as cardboard, paper, some fabrics and even chocolate.

His lab developed a prototype of the chip and his research was published in the March 2024 issue of IEEE Transactions on Terahertz Science and Technology. The research was conducted in collaboration with researchers at Seoul National University and was supported financially by Texas Instruments and the Samsung Global Research Outreach Program.

All energy falls within the electromagnetic spectrum. Forms of energy with shorter wavelengths, such as X-rays, are more energetic and can be harmful to humans and animals when exposed to them in large amounts. Forms of energy with longer wavelengths, such as radio waves, are less energetic and pose less of a risk. Visible light, which the human eye can perceive, falls between short and long wavelengths.

Cameras capture images when a light source, such as the sun, emits light that is reflected off an object. As it travels, the light passes through the camera’s lens and hits millions of tiny photodetectors, which then record the image as an electrical signal.

O’s prototype image sensor chip has no lens and radiates its own energy at a millimeter wavelength that is reflected from objects. Millimeter wavelengths are longer than visible light and infrared waves and shorter than microwaves.

Once the chip sends out the millimeter wave signal, it passes through a material like cardboard, bounces off the object inside, and travels back to the chip. When it reaches the chip, it hits a series of detectors inside the chip, which then create an image.

Matt Reynolds, an associate professor in the Department of Electrical and Computer Engineering at the University of Washington, says we are already somewhat familiar with the technology.

At airports, the TSA uses X-rays to scan bags, but the machines we walk through with our hands above our heads, called stationary passenger screeners, use a signal at a similar wavelength to O’s chip.

The chip is much smaller and does not have the same performance.

Currently, the chip can only be used from within one inch of the object being imaged, but O says the technology could eventually allow the chip to be used from up to 10 inches away.

“If the reach gets too wide, there are real privacy concerns. That can raise all sorts of issues and potentially cause problems. That’s why we really want to limit the possibilities,” O said.

Brian Ginsburg, director of RF and high-speed research at Texas Instruments’ Kilby Labs, who funded this research, echoed O’s comments on privacy.

“At longer distances, you could secretly see what’s in people’s pockets without them knowing, and possibly even see under clothing,” Ginsburg said in an email. “However, at the frequencies used by O’s group, clothing tends to blur any images.”

Reynolds says the imager chip’s applications have safety features that shouldn’t stop us from exploring this technology further.

“Professor O points out (in O’s peer-reviewed paper) that these sensors could also be used for safety purposes, such as preventing self-driving cars or robots from colliding with people,” said Reynolds, who is not involved in O’s research. While the technology would need to be scaled up, Reynolds said it could be used to detect pedestrians in difficult conditions, such as foggy or snowy nights.

O said another application of the chip could be detecting blades or metal objects in chocolate. Ginsburg added the technology could be used to help users see through boxes or envelopes sent through the mail.

He also said the chip could be used to check the quality of finished products or to determine if there are any problems with the coating on drugs. The chip could also be used as a “sophisticated” stud finder, according to Ginsburg and O.

However, it could be a while before we have this imaging technology in our phones. According to Reynolds, it could be another decade

O’s next steps are to further improve the sensitivity of the pixels and increase the number of pixels on the chip from three to dozens or even hundreds. This is necessary to create images and videos in real time and is comparable to increasing the number of pixels on a camera, Ginsburg said.

If the number of pixels increases, the amount of power needed to supply the chip must be adjusted, Reynolds said.

“Almost over 20 years we’ve been working on this. The amazing thing is that the community around us has been able to improve the performance of these pixels by 100 million times, which is phenomenal… When you look at where we’ve come from,” a practical handheld device with the Superman-inspired vision “doesn’t seem that far away anymore,” O said.

Jordan Chapman reports science for The Dallas Morning News as part of a fellowship from the American Association for the Advancement of Science.