A study on development of artificial larynx with PZT ceramics

Various speech production substitutes which aim to reconstruct speech function have been used practically for vocally handicapped persons. However, the substitute vocalizations used presently have problems in clearness and acquisition. We studied improving clarity by sound quality improvement. We paid attention to PZT ceramic as a sound source of an artificial larynx, and we tried to produce an artificial larynx using these PZT ceramics experimentally. We put this artificial larynx into a human being and evaluated its performance. The artificial larynx produced experimentally showed a similar power spectrum to that of the voice of an unhandicapped person. This voice had good clarity in listening estimation. This artificial larynx is composed of two parts: one part is in the body and the other part is the sound source attached outside of the body. This separated type device has biocompatibility and safety, and it is expected that is possible to be practical use in the near future by miniaturization of power supply.