Low-Voltage Stretchable Electroluminescent Loudspeakers with Synchronous Sound and Light Generation
Hyejin Lee, Donghee Kang, Seungse Cho, Young‐Ryul Kim, Youngoh Lee, Sangyun Na, Haryeong Cho, Seungjae Lee, Geumseok Lim, Jeonghee Yeom, Hyunhyub Ko
Abstract
Stretchable sound-in-displays, which can generate synchronous sound and light directly from the display without a separate speaker, allow immersive audio and visual perception even on curved surfaces. In stretchable sound-in-displays, alternating current electroluminescent (ACEL) devices have been used as light-emitting sources owing to their high brightness and stability. However, stretchable ACEL devices that use low dielectric constant (κ) materials require a high operating voltage for generating light and sound. Herein, we demonstrate a stretchable ACEL loudspeaker with a low operating voltage using stretchable high-κ dielectrics and strain-insensitive electrodes. Our device exhibits 87.7 cd/m 2 of luminance and 79.70 dB of sound pressure level at an operating voltage of 120 V and 10 kHz. As the next platform of wearable devices, the suggested ACEL loudspeaker exhibits high-quality synchronous light and sound generation performance even under various types of mechanical deformation, such as finger flexion and wrist bending.