By all accounts, it should have looked like a magic trick.
A small cube floated above a table, shimmering faintly as a person reached out. With a gentle pinch of thumb and forefinger, the cube spun in place — not on a screen, not behind glass, but in the open air.
This was no illusion. It was a hologram, and for the first time, it could be touched.
How a Hologram Works
Holograms are just awesome. For years, Hollywood has captured the public imagination — from Star Wars to Iron Man — but real-life holograms remained mostly passive, untouchable projections. Even the most advanced holographic systems in today’s tech shows or museums have an invisible barrier. You can look, but you can’t touch.
Now, a team of Spanish engineers has lifted that barrier. In a study posted on March 6 to the HAL open research archive, researchers from the Public University of Navarra unveiled a prototype that allows users to physically interact with holograms for the first time — twisting, poking, and even grabbing them with their bare hands.
“What we see in films and call holograms are typically volumetric displays,” said Elodie Bouzbib, co-author of the study. “These are graphics that appear in mid-air and can be viewed from various angles without the need for wearing virtual reality glasses.”
These true 3D visuals — volumetric displays — work by projecting thousands of 2D images every second onto a surface known as a diffuser. The images blend in the viewer’s eye to create the illusion of a floating object. That diffuser must oscillate at incredibly high speeds — nearly 3,000 frames per second — and has always been rigid to withstand the motion.
Until now.
A Soft Touch for Hard Light
“If a hand touches the diffuser while it’s oscillating, it could break the display — or injure the person,” said Asier Marzo, lead author of the study and a computer science professor at UPNA. “We needed something flexible.”
The breakthrough came when the team replaced the rigid diffuser with a flexible, elastic material — one they’re keeping confidential for now. This change made the display safe to touch. But it introduced a new problem: the material deformed when touched, distorting the hologram.
Their solution was to apply real-time correction. By predicting how the elastic diffuser would bend under pressure, the system automatically adjusted the projected images accordingly — maintaining the correct 3D shape in spite of the distortion. It’s a trick of both physics and perception.
The result is a mid-air image that behaves more like a real object. “For example, grasping a cube between the index finger and thumb to move and rotate it, or simulating walking legs on a surface using the index and ring fingers,” the team wrote.
From Fiction to Function
The technology is still experimental. The research has not yet been peer-reviewed, but it will be formally presented later this month at the CHI Conference on Human Factors in Computing Systems in Japan.
Still, the implications are already rippling beyond the lab.
“Displays such as screens and mobile devices are present in our lives for working, learning, or entertainment,” the researchers wrote. “Having three-dimensional graphics that can be directly manipulated has applications in education — for instance, visualising and assembling the parts of an engine.”
And because no headset is required, these displays are inherently collaborative. Multiple users can interact with the same image in real-time — a feature that could make museums and classrooms more immersive, or bring a new dimension to industrial training.
This work builds on previous efforts by companies like Voxon Photonics in Australia and Brightvox in Japan, both of which have developed volumetric displays. But unlike those, the Spanish team’s version doesn’t just allow people to see holograms from multiple angles — it lets them reach into the illusion and change it.
“Humans are used to direct interaction,” said Marzo. “This project enables us to use this natural interaction with 3D graphics to leverage our innate abilities of 3D vision and manipulation.”
It’s a line that might as well have been scripted for Tony Stark. But the research team is clear-eyed about their goals. They’re not building tech for superheroes — they’re building it for everyone.
