Hi, everyone

I have interested in the piezoelectric ultrasonic micro-transudcer
used for micro-loudpeaker but I encoutered some problems about the
relationship between PZT film thickness and sound pressure level(SPL)
 of the loudspeaker.

As we know, SPL is related with two factors: the vibrating area
and the deflection amplitude. For a d31 vibration mode, more thinner
 the PZT film, more the deflection amplitude, so more SPL the
loudspeaker has.

My question is that, for a transducer with both
 the same vibrating area and the same deflection amplitude, more
 thicker the PZT film, more SPL the micro-loudspeaker has? In
another words, is SPL related the thickness of PZT film, i.e. the
 generated force of PZT to overcome the resist of air damping?

And how to simulate or calculate the relationship between PZT
film thickness and SPL?

Thanks for your suggestion very much in advance!
Teng Ma


---------
Graduate Student
School of Electromechanical Engineering
University of Electronic Science and Technology of China
North Jianshe Road, Chengdu, P.R.China