Holograms popping up all around us. Long-dead rapper Tupac Shakur appeared at the 2012 Coachella music festival. HoloLens from Microsoft is trying to replicate the holodeck from Star trek, allowing the user to interact with 3D objects in augmented reality. Startups like Holoxica can create three-dimensional holograms of human bodies for medical imaging.
While some of these light shows are no longer simple lighting tricks, they don’t make it to the holograms, similar to those that we saw in movies like “Star wars”. Technology true holograms are still in the realm of science fiction. And earlier this year, scientists presented innovations that can advance this technology in a few light years ahead.
In a study published in Nature Photonics, a group of scientists from Korea have developed a 3D holographic display, which, in their opinion, works 2600 times better than any existing similar technologies. Meanwhile, scientists from Australia reported in the journal Optica miniature device, which creates the highest quality holographic images to date. The work was published with an interval of three days last month.
Holography — a wide range of science and technology, but it is based on the photographic principle, which records the scattered light from the object. Then this light is reproduced in a 3D format. Holography was first developed in the 1940s, Hungarian-British physicist Dennis Gabor, who received the Nobel prize in 1971 for physics for his invention and development of the holographic method.
Most of the holograms presented static images, but scientists are working on a more dynamic system for the reproduction of a vast amount of information included in the 3D image.
The difference in diffusion
Take the work done by the scientists of the Korean Institute of science and technology (KAIST).
Our ability to produce a dynamic hologram of high resolution — remember Princess Leia, begging for Obi-WAN Kenobi to help the Jedi — currently limited to modulators of the wave front. These devices, spatial light modulators or digital Micromirror device, can control the direction of light propagation.
System imaging with short focal length can only create a tiny image with a wide viewing range. Conversely, a system with a large focal distance can generate an enlarged image with a very narrow range. The best of the technologies of the wavefront modulator is able to create the image one centimeter with a viewing angle of three degrees.
This can be improved through the creation of a complex and cumbersome system using multiple spatial light modulators, for example. But the team from KAIST has come to a simpler solution.
“This problem can be solved by simply connecting the diffuser,” explains Yong Keun, Park, Professor, Department of physics at KAIST. Because the diffuser scatters light, the size of the image and the viewing angle can be increased several thousand times. But there is a problem. Diffuser oil light.
“To use a diffuser as a “holographic lens, it is necessary to carefully calibrate the optical characteristics of each diffuser,” says Park. “For this we use the “method of shaping the wave front”, which provides information about the relationship between the inlet to a diffuser with light and leaving him.”
The Park team have managed to create enhanced three-dimensional holographic image with a viewing angle of 35 degrees in a volume of 2 x 2 x 2 centimeters.
“The improvement in scale, resolution, and viewing angles using our method easily massturbate”, he said. “Because it can be applied to any existing modulator wave front, it can significantly improve the image quality of even the best of the modulator, which will be released on the market.”
The first thing this technology can be used (when completed) in projection displays for car or holographic projections of the smartphone interface, Park says. “Holograms will give us a new experience of communication with electronic devices, and can be implemented with fewer pixels than a three-dimensional holographic display”.
Optics of a new era
At the same time, physicists from the Australian national University presented a device consisting of millions of tiny silicon columns, each 500 times thinner than a human hair. This transparent material is capable of complex manipulations of light, they write.
“Our ability to structure materials on the nanoscale allows to achieve new optical properties beyond the properties of natural materials,” says Sergey Kruk, co-Director of the study. “Holograms, we did demonstrate the significant potential of this technology for use in various applications.”
Scientists say they were inspired by movies like “Star wars”. “We are working with the same physical principles that have inspired science fiction writers,” says crook. He adds that this new material may one day replace the clumsy and heavy lenses and prisms, which are used in other applications.
“With our material, we can create components with the same functionality, but easier and less. This opens up completely new application, starting with the reduction of cameras in a smartphone and ending with the reduction of weight and size complex optical systems in space satellites”.
And now about something else entirely
By the way, about space exploration: can the universe be a hologram? What does this mean for pseudohalogens of Tupac Shakur? And for the rest of the living three-dimensional beings?
Theoretical physicists believe that the observed evidence to support a relatively new theory in cosmology that says that the known universe is a projection of the two-dimensional reality. First launched in 1990-ies the hypothesis inherently contains the idea similar to a regular hologram, when a three-dimensional image encoded in a two-dimensional surface.
Proponents of this theory argue that it can reconcile the two great theories in cosmology. The General theory of relativity explains almost everything that happens on large scale the Universe. Quantum physics perfectly describes small things: atomic and subatomic particles. Work on the topic of the holographic Universe was published in the journal Physical Review Letters.
The researchers used data obtained with instruments that study the cosmic microwave background (CMB). CMB is the afterglow of the Big Bang, which is 14 billion years old. You can see the CMB in the form of white noise to the not tuned TV.
The study showed that some simple quantum field theories can explain almost all the cosmological observations of the early Universe. And also, this work may lead to the emergence of a working theory of quantum gravity, merging quantum mechanics with Einstein’s theory of gravity.
“The key to understanding quantum gravity lies in understanding field theory in one lower dimension,” says lead author Niaes Afshordi, Professor of physics and astronomy at the University of Waterloo. “Holography as the Rosetta stone, the translation of the famous quantum field theories without gravity in the unexplored territory of quantum gravity”.
Difficult. But not fiction.