US researchers are developing a way to turn ordinary pieces of glass into transparent computer displays using attachable plastic sheets full of nanoparticles.
The engineers at the Massachusetts Institute of Technology (MIT) found that embedding silver nanoparticles in glass enabled it to reflect blue light that would normally pass straight through.
They claim that incorporating the nanoparticles into thin, flexible polymer sheets would enable them to turn any normal piece of glass into a transparent projector screen.
This could lead to more useful heads-up displays on windows or vehicle windscreens that – unlike existing technology – don’t require the use of expensive electronics or need users to stand at a precise angle to the screen in order to receive images beamed directly into their eyes.
Silver nanoparticles were used because they were cheap but a combination of other particles would enable the screen to display more colours by reflecting a combination of specific wavelengths.
‘The glass will look almost perfectly transparent because most light is not of that precise wavelength,’ said Prof Marin Soljačić, who co-authored a paper on the research for the journal Nature Communications.
Existing transparent screens tend to use organic light-emitting diodes and transparent electronics directly integrated into the glass, but these systems are complex, expensive and have limited transparency.
Other heads-up displays use a mirror or beam-splitter to project an image directly into the user’s eyes, making it appear that the display is hovering in space somewhere in front of him. But the user must be in exactly the right position to see the image.
The research was supported by the US Army Research Office and the National Science Foundation.