Backplate for microphone

摘要

A microphone has a membrane (20) mounted to vibrate in response to pressure fluctuations, a backplate (30) facing the membrane and being more rigid than the membrane, and circuitry (95) for sensing the vibrations relative to the backplate, the backplate being prestressed and having a geometry such that a response of the backplate to structure borne vibration matches a corresponding response of the membrane. This can help reduce or minimize relative movement between these surfaces caused by structure borne vibration and hence improve the signal-to-noise ratio of the microphone. The geometry can be a hub and spoke arrangement.