Piezoelectric polymer film transducers for communications

Electroacoustic transducers based on piezoelectric PVDF can be used as microphone, receiver, or tone ringer for electronic telephones. The output level of a curved polymer film sound generator was found to depend on material properties (elastic and piezoelectric constants) and film configuration. Transducer elements using double diaphragms operating in push-pull are simple in construction, light weight, and show improved voltage efficiency. Performance characteristics including output level, frequency response, and impedance will be given for microphones, receivers, and tone ringers.