Ever since I was a child I have found myself in (hypothetical and hopeful) holograms of all sorts, which can be manipulated in the air as if they were light objects.
Today a team of researchers from the University of Sussex has found a way to create cutting-edge holograms that you can not only see but also hear and even touch. The best thing, then, is that they did it by drawing on already existing and "ready" technology.
A paper on the scientific discoveries related to this new hologram device (called MATD, Multimodal Acoustic Trap Display) it was published the day before yesterday in the journal Nature.
An ultrasound cage to see…
The device works by using ultrasound waves to trap and move a small, two-millimeter-wide piece of Styrofoam in mid-air. The polystyrene acts as a "brush" that traces the shape of an object in three dimensions while three LED lights spread the classic red, green and blue color combinations on it.
The speed of the "brush" is such that the human eye only sees what it draws - a sort of sequence of frames that moves rapidly like the sheets of a notepad which, as they scroll, compose an animated sequence.
“Our prototype uses a colored particle that can move so fast in space that the naked eye sees only a 3D image suspended in mid-air,” says the researcher Ryuji Hirayama in a Press release.
…feel and touch
The massive use of ultrasound waves allows the device to produce a perfectly audible noise and a physical sensation/response in conjunction with the holograms.
“Although inaudible to us, ultrasound is still mechanical waves, and carries energy through the air”, said the researcher Diego Martinez Plasencia. "Our prototype directs and focuses this energy, which can then stimulate the ears with audio or stimulate the skin.”
The future of holograms
The researchers imagine that future versions of the device will make use of more tiny Styrofoam “brushes” to create even more detailed holograms. And unlike many technologies considered cutting-edge in this field, this one may not have too much difficulty making the leap from the lab to store shelves.
“The MATD was created using low-cost, commercially available components,” says researcher Ryuji Hirayama in a press release. “We believe there is a lot of room to increase its capacity and potential.”
