Inter-element spacing effects on Directivity of sound in a capacitive micro-speaker

The rapid development of technology in multimedia devices requires the development and miniaturization of the smaller devices and systems such as microphones and micro-speakers. Micro speakers play an important role in personal audio devices such as cell phones,laptops and other portable systems. Energy radiated from an acoustic source can be used in multimedia devices, medical and mechanical applications, if it can be directed. In this paper, governing equation of motion of the micro-speakers diaphragm has been introduced andsolved using Galerkin-based numerical procedures. The calculated static and dynamic pull-in voltages have been calculated and validated by previous studies and a good agreement has been achieved among the results. Directional behavior a discrete line array (consists of anumber of drivers) of speakers has been considered under different inter-element space . Moreover, the sound steering has been obtained at desired angle with a variety of inter-element to wave length ratios.

Keywords:

Micro-speaker , Pull-in voltage , Acoustic , Directivity