new dates: December 7 – 11, 2020
Organised by the European Acoustics Association, the Forum Acusticum is a major European conference on acoustics that takes place every three years – this year for the first time as a digital event. Meet our experts virtually, who will present the latest research findings in the field of MEMS loudspeaker development in two presentations.
Interested parties are cordially invited!
Integrated piezoelectric MEMS loudspeakers for in-ear applications
Fabian Stoppel (Fraunhofer ISIT), Andreas Männchen, Florian Niekiel (Fraunhofer ISIT), Daniel Beer, Bernhard Wagner (Fraunhofer ISIT)
This contribution introduces a MEMS-based in-ear headphone system. The core element is a chip loudspeaker manufactured solely using standard MEMS technology. It features multiple piezoelectrically driven bending actuators, which are mechanically decoupled from each other and are directly used for sound generation. In combination with an in-ear housing and dedicated driving electronics, the MEMS loudspeakers enable good performance at small device size. In an IEC 60318-4 ear simulator, for example, sound pressure levels of up to 110 dB are achieved across the entire audible frequency range. In addition, the headphones feature a high electroacoustic sensitivity of about 120 dB/mW, low harmonic distortion and a reproduction range significantly exceeding the audible range. The contribution covers the technology as well as a comprehensive electroacoustic analysis. In addition, the huge development potential concerning future loudspeaker generations will be discussed.
Expedition MEMS Speaker
Daniel Beer, Jan Küller, Tobias Fritsch
There is a high demand for portable sound on the market. Manufactures of headphones, hearing aids, and smartphones have to deal with miniaturization of electroacoustic transducer (micro speakers) size by keeping sound quality and energy efficiency (battery life time) at the same time. Different techniques are known to downsizing transducers. A very successful method is given by the semiconductor industry. The use of the so-called MEMS technology (Micro-Electro-Mechanical-System) leads to great success in applications for microphones and accelerometers. This success has triggered a high interest in the potential of MEMS technology for speaker manufacturing. The presentation gives an overview of the challenge for MEMS loudspeakers. Based on patents, the initial approaches of MEMS loudspeakers will be presented. Finally, some notes will be given for particularities in very small acoustic systems.