BYU study produces 3D images

In the original Star Wars film, R2D2 projects an image of Princess Leia in distress. The iconic scene includes the line still famous 40 years later: “Help me Obi Wan Kenobi, you’re my only hope.”

BYU electrical and computer engineering professor and holography expert Daniel Smalley has long had a goal to create the same type of 3D image projection. In a paper published this week in Nature, Smalley details the method he has developed to do so.

“We refer to this colloquially as the Princess Leia project,” Smalley said. “Our group has a mission to take the 3D displays of science fiction and make them real. We have created a display that can do that.”

First things, first, Smalley says. The image of Princess Leia is not what people think it is: It’s not a hologram. A 3D image that floats in air, that you can walk all around and see from every angle, is actually called a volumetric image. Examples of volumetric images include the 3D displays Tony Stark interacts with in "Iron Man" or the massive image-projecting table in "Avatar."

Dr. Smalley with his student researchers.

Smalley and his coauthors have devised a free-space volumetric display platform, based on photophoretic optical trapping, that produces full-color, aerial volumetric images with 10-micron image points by persistence of vision.

The technique, as described by Nature, “uses forces conveyed by a set of near-invisible laser beams to trap a single particle — of a plant fiber called cellulose — and heat it evenly. That allows researchers to push and pull the cellulose around. A second set of lasers projects visible light (red, green and blue) onto the particle, illuminating it as it moves through space. Humans cannot discern images at rates faster than 10 per second, so if the particle is moved fast enough, its trajectory appears as a solid line — like a sparkler in the dark.”
“In simple terms, we’re using a laser beam to trap a particle, and then we can steer the laser beam around to move the particle and create the image,” said undergrad coauthor Erich Nygaard.

Smalley said the easiest way to understand what they are doing is to think about the images they create like 3D-printed objects.

“This display is like a 3D printer for light,” Smalley said. “You’re actually printing an object in space with these little particles.”

So far Smalley and his student researchers have 3D-light-printed several tiny images: a butterfly, a prism, the stretch-Y BYU logo, rings that wrap around an arm and an individual in a lab coat crouched in a position similar to Princess Leia as she begins her projected message.
While previous researchers outside of BYU have done related work to create volumetric imagery, the Smalley team is the first to use optical trapping and color effectively. Their method of trapping particles and illuminating it with colorful lasers you can see is novel.
“We’re providing a method to make a volumetric image that can create the images we imagine we’ll have in the future,” Smalley said.

How is a volumetric image different than a hologram?

A holographic display scatters light only at a 2D surface. If you aren’t looking at that surface, you won’t see the 3D image because you must be looking at the scattering surface to see the image. A volumetric display has little scattering surfaces scattered throughout a 3D space — the same space occupied by the 3D image — so if you are looking at the image you’re are also looking at the scatters. For this reason, a volumetric image can be seen from any angle.
To see the full Nature study, click here:

//www.nature.com/articles/nature25176

More Information on This Article

Article Source/Further Information

News and Events

Image for Mystery of Haumea's Formation Solved
BYU Physics and Astronomy student Benjamin Proudfoot recently published research in the prestigious journal Nature Communications that solves the mystery of the icy dwarf planet Haumea's formation.
Image for Dr. John Colton: Table Tennis Champion
Dr. John Colton won the 2022 BYU intramural table tennis tournament
Image for Debunking acoustics myths around the Saturn V
When the Saturn V rocket propelled man to the moon in July 1969, the blast from the rocket’s engines was tremendous. Marked by a dazzling display of flames and deafening noise, the monumental event gave rise to widespread claims that the acoustic force of the rocket melted concrete and ignited grass fires miles away. New research from BYU debunks this common myth.
Image for Dr. Aleksandr Mosenkov, new Astronomy faculty
Dr. Aleksandr Mosenkov, new faculty, looks forward to receiving some of the first data from the James Webb Space Telescope to study galaxy formation
Image for Sounding out the Deep: Traci Neilsen’s Trip to the North Atlantic
A recent research adventure took Dr. Traci Neilsen and two students to the North Atlantic Ocean. Neilsen, an associate professor of physics at BYU, and her team apply artificial intelligence to noises in the ocean to classify the seabed.
Image for Reveling in Uncertainty
Despite the inherent time constraints of engaging undergraduate and graduate students in research, Scott Bergeson enjoys teaching this “seek and find” principle to his students, a principle that has become his philosophy for life.
Image for BYU Acoustics Records Artemis Launch
A group of BYU students and professors gathered acoustical recordings of at the world’s most powerful rocket launch.
Image for Kent Gee Recognized by AIAA
Kent Gee is selected as Associate Fellow of American Institute of Aeronautics and Astronautics in their class of 2023
Image for West Mountain Observatory contributes to understand distant galaxy
BYU’s West Mountain Observatory was one of 37 ground-based telescopes throughout the world monitoring the active galaxy that is roughly 1 billion light years away.
Image for Dr. Tim Leishman retires from BYU
Dr. Leishman's time at BYU was filled with great teaching and profound mentoring