Making the invisible visible with terahertz imaging chips

In our recent podcast, we sat down with Dr. Kenneth O. and Dr. Wooyeol Choi , two pioneering researchers who have developed an innovative terahertz imaging chip. Like Superman’s X-ray vision, this breakthrough technology could revolutionize various industries by allowing us to see through objects such as walls, packages, and certain materials.

Introduction to our guests

Dr. Kenneth O is a professor at the University of Texas at Dallas and the director of the Texas Analog Center of Excellence (TxACE). TxACE is a hub for cutting-edge integrated circuit technology advancements funded by the Semiconductor Research Corporation, a consortium of semiconductor companies. Dr. Wooyeol Choi, an assistant professor in the Department of Electrical and Computer Engineering at Seoul National University in Korea, has been an integral part of this research since his time as a postdoctoral researcher at UT Dallas.

Inspiration and development

The terahertz imaging chip was inspired by X-ray vision, though it utilizes terahertz frequencies instead of harmful X-rays. As Dr. Kenneth O explained, “Our work is inspired by X-ray vision, instead of X-rays that can be harmful. That can be harmful to humans.” Instead, the chip operates within the electromagnetic spectrum’s 200 to 400 gigahertz range, which is safe for human exposure.

When asked what inspired the chip, Dr. Kenneth explained that the journey to develop this technology has been long and complex. Dr. O and his team have spent over 15 years refining the chip, improving pixel performance by 100 million times, and incorporating digital signal processing techniques.

This painstaking research has led to a chip that is small enough to be integrated into mobile devices while still providing high-quality images.

How Terahertz imaging works

The basic principle behind terahertz imaging is the emission and detection of high-frequency signals. As Dr. O described, “We have a 300 gigahertz signal source that generates the signals to illuminate whatever object you want to see, and then we pick up the reflected signal to create images. We typically refer to this capability as terahertz imaging.”

Dr. Choi added, “This frequency can be a sweet spot. It is low enough frequency so that you can still go through walls and some nonmetallic materials, but it has a short enough wavelength so that humans or computers can interpret or process it easily.”

The terahertz frequency range allows the waves to penetrate materials like walls and envelopes, providing images without bulky optics. This makes the technology highly suitable for integration into compact devices such as smartphones.

Applications of Terahertz imaging

The potential applications of terahertz imaging are vast and varied. One of the most immediate uses is in package inspection. Dr. O noted, “This technology will allow you to see through walls to locate wires, pipes, and studs. It can also inspect packages, detect hidden defects in materials, and even authenticate documents and currencies.”

The chip could revolutionize the way we handle everyday tasks. Imagine being able to verify the contents of a package without opening it or ensuring that walls are free of hidden defects before renovation work. The implications are significant for the construction, logistics, and security industries.

While the technology has some limitations in the medical field due to its shallow penetration depth into tissues, it can still offer valuable applications. Dr. O mentioned, “One of the areas that I’m excited about is its sensitivity to water in the skin, which can be used to monitor hydration levels. This could be a wonderful capability, especially in medical settings where hydration monitoring is challenging.”

Privacy and ethical considerations

With the ability to see through objects comes the responsibility of ensuring privacy. Dr. O emphasized, “Privacy is of utmost importance because this kind of technology cannot be utilized broadly on mobile devices if you cannot ensure that privacy can be protected.” To address this, the current technology is designed to operate at a very close range, typically up to about 1.18 inches (3 centimeters). This makes unauthorized scanning difficult, as it would be noticeable.

Future iterations aim to extend this range to about 7.87 inches (20 centimeters), which would still be manageable regarding privacy concerns. The technology’s physical limitations also help protect privacy, as creating devices with much longer ranges is technically challenging.

Future developments and market potential

The journey of this technology is far from over. The researchers are working on increasing the number of pixels in the chip and improving the resolution. Dr. Choi explained, “We are certainly going toward the wider field of view and more pixels. Our ongoing goals are improving signal-to-noise ratio, range, resolution, and power consumption.”

The team is also exploring various applications beyond mobile devices. For example, terahertz imaging could be integrated into smart glasses, providing users with augmented vision capabilities. In the automotive industry, the technology could enhance safety features by detecting objects on the road in adverse weather conditions.

While commercialization plans are still in development, the researchers are focused on creating prototypes that can demonstrate the technology’s full potential. Dr. O remarked, “We believe that these are the necessary critical steps to really excite the investment community so that we can take another step toward commercialization.”

The terahertz imaging chip represents a significant leap forward in imaging technology. By harnessing the unique properties of terahertz frequencies, Dr. Kenneth O, Dr. Wooyeol Choi, and their teams have created a tool that can see through everyday obstacles, opening up new possibilities across various fields.

As development continues, we can look forward to a future where this innovative technology becomes integral to our daily lives, making the invisible visible in ways we never thought possible.