This is a science

is scientific American's 60 second science.

I'm Christopher Intalyata.

Got a minute?

There's a scene in Blade Runner, Ridley Scott's

sci-fi classic when Harrison Ford's character, Decard, is about to interview Rachel, played by

Sean Young, to test whether she's a real human or a replicant. On cue, the floor-to-ceiling windows dim, shading the room from the golden sunlight outside.

It was a beautiful Hollywood effect when the movie came out in 1982. And now it may not be that far from reality,

because researchers at Harvard recently designed a material that, with a shot of electricity,

can transform a glass window from transparent to opaque in less than a second.

The team built the window by sandwiching glass between two sheets of a transparent balloon-like

rubber material laced with silver nanowires.

As is, the material is clear, but apply voltage and the nanowires are attracted to each other,

ever so slightly across the glass, which deforms those rubbery sheets just

enough to scatter light, causing the glass to cloud up.

They describe the device in the journal Optics Letters.

Study author Samuel Sheehan, a material scientist, says this smart glass is cheaper than others,

and uses minimal power, much less for example than something like a curling iron.

And since it's flexible and foldable,

he says it could even be used for things like camouflage uniforms,

to switch, for example, from green and brown to white and gray.

This would be very useful when the background landscape suddenly changes such as during early snowfall.

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