A team of Chinese scientists has developed a miniature scanning device that allows for seeing through clothing or certain materials such as cardboard and paper.
According to research published in the journal Advanced Materials, the effect of these glasses is similar to the X-ray vision of the superhero character, but safer for users.
The South China Morning Post reported on December 14 that the significant differentiating feature of these glasses is that they rely on an alternative form of radiation that can penetrate non-conductive materials, excluding water or metals.
X-ray radiation is emitted at levels that are too strong and harmful, potentially causing cell mutations that can lead to cancer. In contrast, terahertz radiation, or T-rays, has longer wavelengths in the electromagnetic spectrum, situated between infrared and microwave radiation. It is weaker than X-rays and therefore safer.
Scientists have been studying terahertz radiation for many decades. However, the equipment used to detect it has been cumbersome, sometimes occupying an entire room and requiring multiple technicians to operate complex processes.
The devices equipped with sensors must be maintained in extremely cold environments. When radiation interacts with these sensors, it disrupts some atoms and releases heat. However, the amount of heat generated is so small that it can only be detected in extremely cold conditions.
T-ray glasses can be used to detect weapons in a crowd. (Photo: Sam Tsang).
The research team, led by Professor Huang Zhiming at the Shanghai Institute of Technical Physics, China, has taken a different approach. They created a “trap” to capture T-rays, using a semiconductor sandwiched between two metal plates. When the radiation strikes the thin film, it generates an asymmetric electromagnetic wave. This wave then pulls electrons from the metal plate to generate an electric current.
This form of radiation cannot be measured digitally with electronic counters. It exists at very high frequencies in the electromagnetic spectrum, requiring scientists to use indirect measurement methods. In this case, by measuring the emitted current, the research team can apply fixed algorithms to accurately model the rays.
According to Huang, the breakthrough with this detection device is that it is the size of a grain of rice, making it easy to attach to mobile devices or integrate into smart glasses. It has sensitivity comparable to large machines occupying entire rooms but is 1,000 times faster. Speed is crucial due to the delay between the moment the rays hit the sensor and the current that is generated. Reduced latency allows for better and more accurate monitoring.
Huang predicts that it will take at least another decade before the first pair of T-ray glasses is launched due to technical obstacles, including the power source. To penetrate fabric, the glasses must emit a beam similar to radar so that the electromagnetic waves can bounce back and be detected.
Currently, scientists have yet to find a power source small enough to integrate into a mobile object. They also need to address power supply issues, as generating T-rays requires much energy, exceeding the capacity of smartphone batteries.
However, Huang is optimistic about the future of this technology, partly due to its potential military applications. With a sufficiently powerful power source, T-rays could be used in radar systems to detect stealth aircraft or in military satellites to transmit large amounts of data.
Huang stated that T-ray radars could “observe” objects from a kilometer away in good weather conditions. He hopes that this range will expand further in the future.
