A technology for producing high-resolution displays that are stretchable and soft like skin has been developed. With its own elasticity and the ability to simultaneously generate sound and light, it is expected to be useful as a next-generation display for wearable devices, mobile devices, and the Internet of Things (IoT).

A research team led by Professor Moon-Ki Choi of the Department of Materials Science and Engineering at UNIST (President Yong-Hoon Lee) announced on the 27th that they have developed "high-resolution patterning technology for stretchable light-emitting layers through stamp surface control." Stretchable light-emitting devices produced using this technology possess flexibility while simultaneously emitting light and sound.

Professor Choi Moon-ki stated, “Although the demand for next-generation displays is increasing, it is difficult to apply patterning processes to conventional light-emitting devices, so we developed a ‘technology for transferring the light-emitting layer through surface energy control.’”

Based on the developed technology, the research team also unveiled a 'visual and auditory dual encryption device' capable of bypassing firewalls using sight and hearing.

Patterning is the act of processing desired circuits or shapes on a substrate. The technology developed by the research team obtains a pattern by copying a patterned light-emitting layer onto an electrode. The existing technique is performed on a viscoelastic stamp that can be peeled off and reattached like tape. Because the film is stably attached, even small patterns can be obtained without distortion.

Through this, patterns with a minimum line width of 150 micrometers (μm) could be obtained, and patterns of various colors (blue, green, white) could also be processed through a repetitive process. The fabricated device exhibited excellent brightness and sound characteristics, and demonstrated stability by maintaining over 95% of its original shape even after more than 5,000 deformation tests.

The research team fabricated a 'visual and auditory dual encryption device' using the developed technology. The visually encrypted image code is designed to be decrypted when power is supplied by a specific user. Additionally, by introducing auditory encryption using sound—an analog signal that is difficult to hack—it is possible to apply a dual firewall system.

Professor Moon-Ki Choi of the Department of Materials Science and Engineering stated, “Through this research, we developed a high-resolution display that generates sound and light simultaneously,” adding, “We have confirmed its potential for application as a next-generation display capable of performing new functions, such as wearable speakers, dual encryption devices, and multi-QR implementations.”

This study was published in the world-renowned scientific journal 'Advanced Functional Materials' on August 14. The research was conducted with support from the National Research Foundation of Korea under the Ministry of Science and ICT's Excellent Young Researcher Program.