The Korea Institute of Machinery and Materials (KIMM) has invented the world's first stretchy meta-display technology, which can stretch up to 25% without causing image distortion. Since 2008, KIMM's Department of Nano-Mechanics has been studying micro-LED transfer technology. This was accomplished by metamaterials having unique mechanical characteristics which do not exist in nature, as well as metamaterial design and production techniques.
When stretched lengthwise, most stretchy materials in nature, such as rubber, shrink in width resulting in image distortion. This was also true in the case of stretchable screens made of rubber.
On a circuit board, the KIMM research team used mechanical metamaterials with a negative Poisson's ratio. When a material is stretched lengthwise, the Poisson's ratio describes how much it decreases in width. Stretching a mechanical metamaterial with a Poisson's ratio of -1 lengthwise has the same effect as stretching at the same ratio widthwise. As a result, images on a display made with such materials are not skewed.
The team combined mechanical metamaterial designs and manufacturing technology with the world's biggest large-area micro-LED roll transfer technology to create this breakthrough meta-display manufacturing method. The study team wants to do follow-up research on micro-LED panels for ultra-realistic metaverses based on the positive outcomes of this project.
Promoting practical use of the technology
Dr. Bongkyun Jang stated that his team has used meta-structures to solve the core issue of image distortion in stretchable displays, and that the researchers will continue to seek the commercialization of meta-display technologies so that they can be used in a variety of electronic products in the future.
The recently developed adaptable meta-display technology is expected to help diversify platforms for mobile electronic devices like phones and tablets. Medical gadgets, cosmetics and healthcare all benefit from such displays since they can stick to the skin of the human body without wrinkles.
The research is published in Advanced Functional Materials.