A microphone is formed to have a diaphragm that is configured to improve signal to noise ratio. To that end, the microphone has a backplate having a hole therethrough, and a diaphragm movably coupled with the backplate. The diaphragm has a bottom surface (facing the backplate) with a convex portion aligned...http://www.google.es/patents/US7961897?utm_source=gb-gplus-sharePatente US7961897 - Microphone with irregular diaphragm
