Removal of the earpiece has already been done by the origial Xiaomi Mi Mix ( review ), that used a "cantilever piezoelectric ceramic
acoustic technology", which vibrates the internal metal frame of the device for producing sound.
The piezoelectric phases of the OPCM sensor are cut from the same monolithic and already polarized P-51 piezoelectric ceramic
plate to ensure that the piezoelectric material properties are consistent.
Composites comprised of piezoelectric ceramic
fillers embedded within a matrix material have been proposed for many applications such as hybrid energy systems [24, 25], battery separator materials , energy harvesting, energy conversion storage [6, 24, 25, 27], and capacitors [35, 36].
The advantage of SBN nanocrystals is generally attractive for some device applications, such as thin film devices , optical sensors , and piezoelectric ceramic
In order to make the output displacement large and precise, Cuihong Li of Tsinghua University  used GMA as the driving source and piezoelectric ceramic
as a clamp.
The idea of using a composite material consisting of an active piezoelectric ceramic
fibrous phase embedded in a polymeric matrix phase has been investigated by a number of researchers.
Since most polymers have a lower dielectric constant compared with piezoelectric ceramic
materials, most of the applied electric field will pass through the lower dielectric constant phase.
Developed by a team led by Canan Dagdeviren, at the time a doctoral candidate at the University of Illinois, these piezoelectric ceramic
nano materials could enable future pacemakers to convert the body's autonomic physical motion to electrical power by bending and stretching through direct contact with the beating heart, rising diaphragm, or expanding lungs.
However, it can be reduced significantly, if advanced nanotechnologies are used to produce piezoelectric ceramic
The team starts with piezoelectric ceramic
or crystal and uses lapping and polishing machines to thin the material, and a dicing machine built for the semiconductor industry to cut it.