Angle-dependent holograms made possible by metasurfaces

Recently, a research team from Pohang University of Science and Technology (POSTECH) used metasurfaces to create angle-dependent holograms with multiple functions. This technology allows the hologram to display multiple images based on the observer’s viewing angle. gave Results It was published in Nanoliters.

Objects can appear different depending on the position of the viewer, a concept that can be used. Holographic technology To create cinematic and realistic 3D holograms that project different images based on viewing angle. However, the current challenge lies in controlling the angular propagation of light, making the use of nano-optics in this context a complex endeavor.

The team tackled this challenge by taking advantage of metasurfaces, synthetic nanostructures capable of precisely manipulating the properties of light. These metasurfaces are incredibly thin and lightweight, about one-hundredth the thickness of a human hair, making them promising for applications in miniature displays such as virtual and augmented reality devices.

Through the use of metasurfaces, the team devised a system that controls light to deliver only a specific phase of information at a specific angle, resulting in diverse images based on the angle of incidence.

In their experiments, the team’s metasurface produced separate 3D holographic images at angles of both +35° and -35° for left circular polarization. Notably, the team managed to produce a variety of images. Event lighting using a single metasurface, depending on the specific polarization. In particular, holographic displays have been widely demonstrated. Viewing angle of 70° (±35°), enabling observers to perceive three-dimensionality. Hologram from different directions.

A research team consisting of Professor Jinsik Rao from the Department of Mechanical Engineering and Department of Chemical Engineering and Ph.D. candidate Joohoon Kim from the Department of Mechanical Engineering at POSTECH Metasurface Display technology.

Professor Jinsik Rowe, who led the research, explained, “We have successfully achieved an impressive feat. Display “We expect this technology to play a major role in the commercialization of technology in virtual and augmented reality displays, encrypted imaging, information storage and other applications,” he added.