As seen in movies, new meta-hologram can be used as a communication tool

January 28, 2020

Hologram techniques are already used in our everyday life. A hologram sticker to prevent from counterfeiting money, Augmented Reality navigation projected in front mirror of a car to guide directions, and Virtual Reality game that allows a user to play in a virtual world with a feeling of live are just a few examples to mention. Recently, thinner and lighter meta-hologram operating in forward and backward directions has been developed. As seen in the movie, Black Panther, people from Wakanda Kingdom communicate to each other through the hologram and, this specific movie scene seems to become reality soon that we can exchange different information with people from different locations.

Junsuk Rho, professor of POSTECH Mechanical Engineering and Chemical Engineering Department with his student, Inki Kim developed a multifunctional meta-hologram from a monolayer meta-holographic optical device that can create different hologram images depending on a direction of light incident on the device. Their research accomplishment has been introduced as a cover story in the January 2020 issue of Nanoscale Horizons.

Televisions and beam projectors can only transmit intensity of lights but holographic techniques can save light intensity and its phase information to play movies in three-dimensional spaces. At this time, if metamaterials are used, a user can change nano structures, size, and shapes as desired and can control light intensity and phase at the same time. Meta-hologram has pixel sizes as small as 300 to 400 nanometers but can display very high resolution of holographic images with larger field of view compared to existing hologram projector such as spatial light modulator.

However, the conventional meta-holograms can display images when incident light is in one direction and cannot when light is in the other direction.

To solve such a problem, the research team used two different types of metasurfaces.1) One metasurface was designed to have phase information when incident light was in the forward direction and the other one to operate when light was in backward direction. As a result, they confirmed that these could display different images in real-time depending on the directions of light.

In addition, the team applied dual magnetic resonances and antiferromagnetic resonances, which are phenomena occurring in silicon nanopillars, to nanostructure design to overcome low efficiency of the conventional meta-hologram. This newly made meta-hologram demonstrated diffraction efficiency higher than 60% (over 70% in simulation) and high-quality and clear images were observed.

Furthermore, the new meta-hologram uses silicon and it can be easily produced by following through the conventional semiconductor manufacturing process.

The meta-hologram operating in both directions, forward and backward, is expected to set a new hologram platform that can transmit various information to multiple users from different locations, overcoming the limits of the conventional ones which could only transmit one image to a limited location.

Junsuk Rho who is leading research on metamaterials said, 'Microscopic, ultrathin, ultralightweight flat optical devices based on a metasurface is an impressive technique with great potentials as it can not only perform the functions of the conventional optical devices but also demonstrate multiple functions depending on how its metasurface is designed. Especially, we developed a meta-hologram optical device that operated in forward and backward directions and it could transmit various visual information to multiple users from different locations simultaneously. We anticipate that this new development can be employed in multiple applications such as holograms for performances, entertainment, exhibitions, automobiles and more."
This research was supported by the National Research Foundation of Korea under the grants of Mid-career Research Program, Global Frontier Project, Regional Leading Research Center, Engineering Research Center, Future Materials Discovery Project and Global PhD fellowship funded by the Ministry of Science and ICT of the Korean government.

Pohang University of Science & Technology (POSTECH)

Related Hologram Articles from Brightsurf:

An ultrasonic projector for medicine
A chip-based technology that modulates intensive sound pressure profiles with high resolution opens up new possibilities for ultrasound therapy.

Instantaneous color holography system for sensing fluorescence and white light
The National Institute of Information and Communications Technology (NICT), the Japan Science and Technology Agency (JST), Toin University of Yokohama, and Chiba University have succeeded in developing a color-multiplexed holography system by which 3D information of objects illuminated by a white-light lamp and self-luminous specimens are recorded as a single multicolor hologram by a specially designed and developed monochrome image sensor.

Study demonstrates feasibility of hologram technology in liver tumor ablation
Data from one of the first clinical uses of augmented reality guidance with electromagnetically tracked tools shows that the technology may help doctors quickly, safely, and accurately deliver targeted liver cancer treatments, according to a research abstract presented during a virtual session of the Society of Interventional Radiology's 2020 Annual Scientific Meeting on June 14.

Lightning fast algorithms can lighten the load of 3D hologram generation
Tokyo, Japan - Researchers from Tokyo Metropolitan University have developed a new way of calculating simple holograms for heads-up displays (HUDs) and near-eye displays (NEDs).

Black holes? They are like a hologram
Spherical, smooth and simple according to the theory of relativity, or extremely complex and full of information as, according to quantum laws, Stephen Hawking used to say?

A thin lensless camera free of noise
Scientists from Tsinghua University in China and MIT in the US report that applying a compressive sensing algorithm can significantly improve the quality of lensless imaging.

Seeing with electrons: Scientists pave the way to more affordable and accessible cryo-EM
In recent years, a powerful technology called cryogenic electron microscopy (cryo-EM), where flash-frozen samples are embedded in glass-like ice and probed by an electron beam, has revolutionized biomolecule imaging.

Witnessing the birth of baby universes 46 times: The link between gravity and soliton
Scientists have been attempting to come up with an equation to unify the micro and the macro laws of the universe; quantum mechanics and gravity.

As seen in movies, new meta-hologram can be used as a communication tool
Junsuk Rho and his research team developed a multiplexed meta-hologram device operating at visible light.

CUHK Faculty of Engineering develops novel imaging approach
By combining a compressive sensing algorithm with a digital holographic microscope, Prof.

Read More: Hologram News and Hologram Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to