Transparent displays have a variety of potential applications — such as the ability to see navigation or dashboard information while looking through the windshield of a car or plane, or to project video onto a window or a pair of eyeglasses. A number of technologies have been developed for such displays, but all have limitations.

The glass remains transparent enough to see colors and shapes clearly through it, while a single-color display is clearly visible on the glass. (Chia Wei Hsu and Bo Zhen/MIT)
Now, researchers at MIT have come up with a new approach that can have significant advantages over existing systems, at least for certain kinds of applications: a wide viewing angle, simplicity of manufacture, and potentially low cost and scalability.

The secret to the new system: Nanoparticles are embedded in the transparent material. These tiny particles can be tuned to scatter only certain wavelengths, or colors, or light, while letting all the rest pass right through. That means the glass remains transparent enough to see colors and shapes clearly through it, while a single-color display is clearly visible on the glass.

Such displays might be used, for example, to project images onto store windows while still allowing passersby to see clearly the merchandise on display inside, or to provide heads-up windshield displays for drivers or pilots, regardless of viewing angle.

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