Australian researchers have invented a film that will allow a person to see almost as well in the dark as during the day. Glasses with such a film would be much less bulky and more complex than existing night vision devices. Researchers believe this will change people’s lifestyle, habits and skills.

Today, night vision devices convert radiation (photons) in the infrared spectrum into visible images using a multi-stage system. Photons pass through the lenses into an electron tube where a photocathode converts the photons into electrons. The electronic tube then produces an enhanced stream of electrons that fall on the screen with phosphor and excite the glow, reproducing the scene. More complex and sensitive devices require cooling to eliminate background noise. As a result, even the most advanced night vision devices are bulky and heavy.

Researchers at the Australian National University’s ARC Center of Excellence for Transformation of Meta-Optical Systems (TMOS) have created the thinnest food-grade coating for eyeglass or headphone lenses that instantly converts infrared photons into visible spectrum photons. This is achieved using pumping or a reference beam, so it is impossible to do without a sticker consisting only of an “infrared” film on the glass. You need a device in the form of a headset, but in any case it will be simpler and easier than modern night vision devices.

In the new device, infrared photons pass through a metasurface with resonance properties. The metasurface is made of lithium niobate. The metasurface material, together with the pump beam, increases the energy of the photons and converts them into the visible spectrum, bypassing the process of converting photons into electrons, amplifying and bombarding the screen with a phosphor. Moreover, the proposed solution freely passes through the visible range of light, complementing the visible details of the image that are not visible in ordinary light. Even though it is green, which is the most sensitive to the human eye, like night vision devices, the picture is more saturated with details. In the future, night vision promises to be colorful.

The metasurface developed by scientists consists of a thin film and can be placed on ordinary glasses in eyeglass frames. It weighs less than one gram. Scientists remain silent about the mass of additional equipment required for the operation of the glasses. But even if it does not seem compact at the moment, modern semiconductor lasers can be very, very small, and therefore night vision may eventually become available to ordinary people in their daily lives, work or leisure.