Researchers in the UK have designed a new type of display that could make real-time holograms a reality, to be used on billboards, in movie theatres, or maybe even on our own televisions one day.
When you look at a photograph or a regular display, the light bounces right back to your eyes with very little distortion. But when you’re looking at a hologram, you’re looking at an image that’s been created by light bouncing off a specially grooved surface. Standing inside this artificially-generated light field, you will see the resulting image as separate from the surface it’s being projected from.
While holograms have been a mainstay in sci-fi films for decades, in reality, they’ve been a really difficult thing for scientists to master. This is because in order to change a holographic display in real-time, you need to take control of every pixel in the display, and that’s not something many display technologies are equipped for. Plus holograms are extremely data-heavy displays, so the technology needs to be able to process vast amounts of information very quickly in order for it to work.
But now researchers from the University of Cambridge have figured out how to overcome these challenges by applying patterns of nanostructures that act like tiny optical antennae in the display, which can be manipulated using streams of liquid crystals. This allows for the optical properties of every single pixel to be adjusted and changed, so while they won't allow us to project a hologram of ourselves in a Skype call, we could project holograms of recorded images, and change them on the fly.
"In a typical liquid crystal on silicon display, the pixels’ electronics, or backplane, provides little optical functionality other than reflecting light," lead researcher and engineering PhD student, Calum Williams, said in a press release. "This means that a large amount of surface area is being under-utilised, which could be used to store information."
Williams’ team managed to get far greater control over their holographic display by taking advantage of a phenomenon known as plasmonics - how light interacts with the electrons that float freely around in metal materials. In the past, displays that used plasmonics do so with passive optical antennas, which didn’t allow for any adjustments once they were put in place. But Williams and his colleague are able to use their antennae to adjust the pixels and change which holographic image is being projected. The team published the results in the journal Physica Status Solidi.
"Optical nanoantennae produce a strong interaction with light according to their geometry," said one of the team, Yunuen Montelongo. "Furthermore, it is possible to modulate this interaction with the aid of liquid crystals."
Along with flying cars and hoverboards, holograms are definitely one of the top technologies that the movies told us we'd have way before it was even remotely feasible. I really hope this research amounts to something, because just once, I would like the crazy futuristic thing we were promised in '80s movies to be a reality. We're counting on you, scientists!