Researchers at the Public University of Navarra (UPNA) have achieved a significant advancement in holographic technology.
Guided by Dr. Elodie Bouzbib and comprising members such as Iosune Sarasate, Unai Fernández, Manuel Lopez-Amo, Ivan Fernandez, Inigo Ezcurdia, and Asier Marzo, this team has managed to develop three-dimensional images that hover in space—images which can also be interacted with through touch and manipulation by hand.
What we often depict as holograms in movies actually refers to volumetric displays," explained Bouzbib, who was the primary contributor to this research. "These images materialize in free space and allow viewing from multiple perspectives without requiring VR headsets. Such representations are referred to as genuine 3D. graphics .”
She mentioned that this type of presentation encourages an "approach-and-engage" method. She pointed out that these displays are notably engaging because they enable the 'approach-and-engage' concept, which allows users to just walk up to a device and begin interacting with it right away.
This accomplishment pushes the boundaries well past current commercial prototypes. While companies such as Voxon Photonics and Brightvox Inc. provide volumetric displays, these solutions do not enable direct interaction with the hovering visuals. This innovative project alters that dynamic.
Asier Marzo, the chief researcher, said, "Direct interaction involves using our hands to grasp and move virtual objects."
He added, “We are used to direct interaction with our phones, where we tap a button or drag a document directly with our finger on the screen – it is natural and intuitive for humans. This project enables us to use this natural interaction with 3D graphics to leverage our innate abilities of 3D vision and manipulation.”
How the floating 3D display works
This innovation originates from the InteVol project, spearheaded by UPNA and financed by the European Research Council (ERC). The ERC backs premier-level research across the European Union.
Volumetric displays function by projecting imagery onto a swiftly moving component known as a diffuser. Here, the diffuser moves back and forth extremely quickly—at a rate of 2,880 frames each second. Due to the phenomenon of persistence of vision, our eyes perceive these overlapping images as a single cohesive image. 3D object floating in mid-air.
However, there is an issue. Conventional diffusers tend to be inflexible. Making contact with your hand against the movable part might cause damage or injury. Therefore, the group swapped out the solid sheet for a flexible version instead. After testing multiple substances, they aimed to achieve the ideal equilibrium between operational security and clear visibility.
However, switching to elastic materials came with its challenges. “Elastic materials deform and require image correction,” Bouzbib notes. Still, the team developed a working system that allows for natural interaction.
Currently, users have the ability to zoom and shift a three-dimensional cube or mimic walking movements with their fingertips. "As an illustration, one could grip a cube between the index finger and thumb for rotation and movement, or use the index and ring fingers to imitate walking strides across a surface," they explain. illustrated .
Practical applications in educational settings like classrooms, as well as in cultural institutions such as museums, among others.
The potential uses for this technology are extensive. "Screens like those found in computers, smartphones, and tablets accompany us throughout our work, studies, and leisure time. The ability to interact with three-dimensional images could revolutionize educational practices—such as enabling students to visualize and assemble components of engines," explained the research team.
It's not limited to individual users alone. These 3D displays can be utilized simultaneously by several individuals without requiring any virtual reality headgear. Thus, they are ideal for cooperative environments.
"Museums" are an area that could see immediate benefits, according to them. They mention visitors would be able to easily come close and engage with the material.
The document is published on the HAL open-access research archive, and there is also a related video. explaining The results have gone live on YouTube. The team will be presenting their findings at the CHI 2025 conference in Yokohama, Japan, between April 26 and May 1.