Study on the Characteristics of Acoustic Radiation of Microspeaker Associated with Pattern of Diaphragm with Finite Element Method

Abstract

The objective of this study is to investigate the acoustic radiation of Microspeaker based on various pattern geometries of diaphragm. The influence of first resonant frequency (f0) is discussed, as are the radiation efficiency (SPL) and impedance curve (IMP). First, microspeaker geometry was reconstructed with CAD software (Creo). Four geometric pattern parameters, width, angle, depth, and quantity, of microspeaker diaphragm were defined and simulated with commercial finite element software - COMOSL Multiphysics. Results showed that the quantity and depth of pattern significantly influenced on the acoustic radiation, especially at lower frequencies. The stiffness of diaphragm decreased with increases in quantity and depth of pattern. In addition, f0 for both conditions shifted to lower frequency and bandwidth of microspeaker was extended. Increasing the angle of pattern, resulted in more solid diaphragm and slight increase in efficiency.