npj Flexible Electronics (Mar 2025)
Dynamic bendable display with sound integration using asymmetric strain control of actuators with flexible OLED
Abstract
Abstract Flexible electronics demand multifunctional human-machine interfaces (HMIs) and organic user interfaces (OUIs). Existing deformable displays often rely on mechanical wires or hinges, limiting their thinness and flexibility. Incorporating sound features typically requires extra components, complicating design. In this study, we developed a lightweight, multifunctional display with a multi-shape bendable design and integrated sound capabilities. Using asymmetrical strain engineering on poly(vinylidene fluoride) (PVDF), we achieved bidirectional and complex deformations through electrical signals, eliminating the need for mechanical hinges. The PVDF actuator enables simultaneous sound emission and intricate shape transformations through rapid actuation and vibration. This design maintains the thinness and flexibility of organic light-emitting diode (OLED) technology. By controlling strain through PVDF polarization and applied electric field, we realized varied shape transformations and integrated these functions into a practical 6-inch OLED display. This approach enhances the functionality of flexible displays, expanding possibilities for future applications in flexible electronics.