Piezoelectric crystal microbalance device
AssigneeO-Sense AB
InventorsMichael Rodahl, Fredrik Hook, Anatol Krozer, Bengt Kasemo
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Abstract
A device and a process for measuring resonant frequency and dissipation factor of a piezoelectric resonator are presented. After exciting the resonator to oscillation, the driving power to the oscillator is turned off after the decay of the oscillation of the resonator is recorded and used to give a measure of at least one of the resonators properties, such as dissipation factor, changes in the dissipation factor, resonant frequency and changes in the resonant frequency.
Claims20
A device for determining properties of a piezoelectric resonator, wherein a piezoelectric crystal is connected to a driving apparatus in order to make said crystal oscillate, said device comprising:
- means for exciting the crystal to oscillation using a driving power supplied by said driving apparatus,
- means for turning off the driving power to said crystal,
- means for recording the decay of an oscillation amplitude and a resonant frequency of said crystal as a function of time, and
- means for using said recorded decay to measure at least one of a dissipation factor of said crystal and changes in said dissipation factor, and at least one of a resonant frequency of said crystal and changes in said resonant frequency.
A method for determining properties of a piezoelectric resonator wherein a piezoelectric crystal is connected to a driving apparatus in order to make said crystal oscillate, said method comprising:
- exciting the crystal to oscillation using a driving power supplied by said driving apparatus,
- turning off the driving power to said crystal,
- recording decay of an oscillation amplitude and a resonant frequency of said crystal as a function of time, and
- using said recorded decay to measure at least one of a dissipation factor of said crystal and changes in said dissipation factor, and at least one of a resonant frequency of said crystal, and changes in said resonant frequency.
Dependencies are inferred from the claim text.