We all remember the iconic Princess Leia hologram from Star Wars: A New Hope where Carrie Fisher uttered the iconic phrase, “Help me, Obi-Wan Kenobi. You’re my only hope.” Star Wars: The Last Jedi even made a cute little callback to that scene, but did you know that we might actually soon have access this kind of technology?
Researchers at Bringham Young University (BYU) in Provo, Utah, have created what they call a “photophoretic-trap volumetric display” that creates “volumetric images” at a point in space rather than on a screen, essentially creating a picture in thin air that is “visible from almost any direction and [is] not subject to clipping.” If this device can be likened to anything, it would be closer to a 3D printer than film projector, albeit a printer that uses light and cellulose particles instead of plastic filaments.
When I said the volumetric display uses light, I meant is lasers, which trap cellulose particles and force them to move in various directions. At the right speeds (and with blue, red, and green lasers), the particles produce images that float in midair. Unlike a hologram in real life, people can view these images at any angle. In fact, according to the BYU researchers, the holograms in movies such as Star Wars and Iron Man are in actuality volumetric images. Holograms are 3D images projected through 2D screens and can only be viewed from so many angles, which doesn’t make them truly three-dimensional. Characters in the Star Wars movies could view the Princess Leia “hologram” from conceivably any angle, which makes it a volumetric image.
While BYU’s breakthrough sounds impressive, reality is sadly a little more sober. The researchers were limited to creating simple images, such as butterflies, prisms, and a low-resolution image of Princess Leia (because of course you have to make one of those). Furthermore, the volumetric images were very small — not much bigger than the head of a pin — and difficult to capture on film. But, the researchers have demonstrated that a piece of technology we thought was purely science fiction is not just possible, it’s buildable today. Granted, scientists are going to have to create upgrades and modifications to make volumetric images large enough to be viewable without a zoom lens, but the groundwork is all there. Plus, once we perfect this technology, perhaps it can be applied to other uses. With the right particles and lasers, maybe we can create Star Wars‘ other iconic piece of technology: the lightsaber.
If you are interested in learning more about BYU’s photophoretic-trap volumetric display, you can read the paper published in Nature, although you will need a subscription.