"Switch Freely Between 2D and 3D Without Glasses"... Just Attach to Smartphone: The Arrival of 'Metalens' [Reading Science]

Joint Development by POSTECH and Samsung

Published in Nature, Viewing Angle Expanded Sixfold

If a thin lens film is simply attached to the surface of a smartphone screen, it becomes possible to freely switch between two-dimensional (2D) and three-dimensional (3D) images without glasses—a next-generation display technology that has been realized for the first time in Korea. This lens changes the direction of light according to electrical signals, either displaying a 2D image as it is or producing a stereoscopic image, and successfully addresses both the narrow viewing angle and image quality degradation that have been limitations of existing 3D technologies.

The Ministry of Science and ICT announced that the research team led by Professor Joonseok Noh at Pohang University of Science and Technology and Samsung Electronics Samsung Research have developed, for the first time in the world, a technology that allows free switching between 2D and 3D using a single "metalens."

Metasurfaces can realize thin and lightweight lenses. They are advantageous for miniaturizing smartphone cameras, AR/VR devices, and wearable displays. Provided by Pixabay.

This research was published in the international journal Nature on April 23, 2026 (Korean Standard Time).

Viewing Angle Expanded from 15 to 100 Degrees... Breaking Barriers with an Ultra-Thin Lens

Demand for 3D displays is rapidly growing in fields such as virtual reality (VR), augmented reality (AR), and medical imaging. However, in reality, most content consumption—including text and video—remains 2D. As a result, technology enabling seamless switching between both modes on a single device has become a key challenge for the industry.

Actual meta-lens product (left) and the arrangement of the nano structures on the meta-surface that function as a lens (right). Provided by the research team.

Existing glasses-free 3D technologies had a very narrow viewing angle of around 15 degrees, allowing only one person directly in front of the screen to see the effect, and suffered from degraded 2D image quality due to their 3D-specific design.

The research team overcame these challenges by using a "metalens" that precisely controls light through a nano-structured surface. This lens, designed with an ultra-thin 1.2mm structure, can switch between concave and convex modes according to the applied voltage, enabling users to freely toggle between 2D and 3D modes.

When no voltage is applied, the lens displays a high-resolution 2D image without distortion. When voltage is supplied, it creates a stereoscopic image with an ultra-wide 100-degree viewing angle. This is about six times wider than previous technologies, allowing multiple people to view 3D images simultaneously from various positions.

"Attach Like a Sticker"... Expansion from Mobile Devices to Advertising

In particular, this metalens operates simply by being "attached" to the screen of a smartphone or tablet, ensuring high compatibility with existing displays.

The research team expects that, beyond mobile devices, this technology can be expanded to a wide range of industries, including medical imaging, large-scale outdoor advertising, and smart spaces.

This conceptual diagram shows the structure that switches 2D and 3D images as the characteristics of the metalens change according to the state of the polarization controller. In the On state, it operates as a concave lens to produce clear 2D images, and in the Off state, it switches to a convex lens to realize 3D images with a 100-degree wide field of view. Image provided by Samsung Electronics Newsroom. Caption: Professor No Junseok, Pohang University of Science and Technology (POSTECH).

This research is significant in that it not only demonstrated the technology but also presented its commercialization potential. The research team also announced a mass production process for metalenses at the same time, thus securing both the core technology and large-scale manufacturing capabilities.

Professor Joonseok Noh at Pohang University of Science and Technology commented, "The ultra-thin metalens has proven its practical potential as a next-generation display platform," adding, "It will contribute to securing foundational technology with broad applications, from mobile devices to industrial uses."

Kim Sungsoo, policy chief for R&D at the Ministry of Science and ICT, stated, "We will strengthen our support to enable researchers to achieve global results through continued investment in basic research."

This content was produced with the assistance of AI translation services.