Engineers at MIT have developed a new way to make extremely thin, flexible layers of electronic material—what they call “electronic skin.”
This breakthrough could lead to a new generation of lightweight night-vision glasses, as well as flexible sensors, transistors, and other advanced devices.
The team demonstrated their technique by creating the thinnest ever membrane of a heat-sensing material called pyroelectric material, which produces electricity when it detects changes in temperature.
Their new film is just 10 nanometers thick—about 10,000 times thinner than a human hair—and can sense even the slightest temperature changes across the far-infrared spectrum.
Current night-vision devices are heavy and bulky because they need cooling systems to work properly.
In contrast, the new pyroelectric film can detect heat without needing any cooling at all. This could lead to the creation of lightweight, portable night-vision glasses that are much easier to wear and use.
The research team, led by MIT graduate student Xinyuan Zhang and Associate Professor Jeehwan Kim, published their results in Nature.
The new film could also have wide applications beyond night vision. It could be used for environmental sensing, biological monitoring, and even studying far-off stars that emit infrared radiation.
The researchers developed a method they call “lattice lift-off” to create their ultrathin films. Normally, making flexible electronics involves growing a material on a crystal base, separated by a layer of graphene that acts like nonstick Teflon.
But in this case, the team found that the heat-sensing material they used, called PMN-PT, could be grown directly on a crystal substrate and still peel off easily. The secret was the element lead, naturally present in PMN-PT.
Lead atoms have strong electron-attracting properties, which prevent tight bonding with the surface and allow the film to lift off smoothly without damage.
Using this discovery, the team created an array of 100 tiny heat-sensing pixels on a chip. They found the new material could detect extremely small temperature changes and respond to a broad range of infrared wavelengths, making it even more sensitive than some current night-vision technology.
Traditional night-vision devices rely on photodetector materials that need to be cooled to very low temperatures, often with bulky equipment. These devices detect heat by measuring electron jumps caused by temperature changes.
However, environmental noise can interfere with this process, requiring extra cooling to ensure accuracy. The new pyroelectric film works differently and does not suffer from the same problems, eliminating the need for heavy cooling systems.
This innovation could be a game-changer not just for soldiers and emergency workers who rely on night vision, but also for autonomous vehicles that need to see through darkness, rain, or fog. The films could also be used for real-time gas detection and early failure detection in electronics by sensing tiny heat changes.
The team plans to continue developing the technology, integrating the ultrathin films into complete night-vision systems and testing them in a variety of conditions.
Supported by the U.S. Air Force Office of Scientific Research, this research points toward a future where night-vision goggles are no heavier than a pair of regular glasses.
