<p>➀ Researchers from POSTECH have developed the world's first smartphone-sized OLED panel that can change shape and function as a speaker without mechanical parts, offering new possibilities for smartphones, cars, and wearables.</p><p>➁ The technology integrates an ultra-thin piezoelectric polymer actuator with a flexible OLED panel, enabling both shape transformation and sound production through electrical signals, eliminating the need for mechanical hinges or external speaker modules.</p><p>➂ The innovation demonstrates stable shape transformations and clear sound production on a smartphone-sized OLED panel, paving the way for next-generation smart displays with integrated audio capabilities.</p>