Zheyao Wang wrote:

> Dear All,
>
> There are several papers on using piezoelectric materials, such as ZnO and
PVDF,
> in audio frequency microphone applications. Since it is evident that PZT has
superior
> features to ZnO and PVDF, why there is no one to use PZT in audio microphones?
> Are there some fatal disadvantages determining that PZT is not possible in
audio
> applications?
>

There may be some reasons:

1. Impedance too high.
2. Necessary thickness for audio frequencies is too large.
3. But probably the most important reason is: electret membrane microphones are
easier to make,
cheaper etc.

I think, that it would be possible to use PZT in microphones, but somebody must
propose an idea,
that would work properly. If this makes sense is open question.


Wieslaw Bicz

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