Page 13 - Vibrations 3

Got to be careful handing lithium

niobate, a temperature change causes

the crystal to expand – charge builds up

– bit of a shock!

This material has two refractive indices,

ordinary and extraordinary which can be changed by

applying an electric field to it.

Typical geometry of a accelerometer which is attached to

a vibrating surface.

The seismic mass compresses the piezoelectric material

and it produces a voltage which is proportional to the

stress on it.

There is a compression mode, a shear mode and a Flexure

mode – they all stress the piezoelectric material.

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