How a piezo actuator works in high frequency nanopositioning

KVISTGAARD, Denmark - Aug. 10, 2015 - PRLog -- What is a high frequency nanopositioning system?

Piezoelectric actuators are used for high frequency nanopositioning, where a small displacement amplitude with a fast response is required. This is the case for example for metrology applications or for the vertical positioning of an AFM (Atomic Force Microscope) probe. In an AFM, the probe has to follow the surface of a sample, either in contact or at a small distance (few nanometers). This requires very fine positioning with sub-nanometer resolution and very low noise. Furthermore, the high resonance frequency allows an improved stability of the control loop, enabling faster imaging.

How does the piezo actuator work in high frequency nanopositioning?

High frequency nanopositioning employs piezoelectric elements or stacks with direct action. This means that the actuator is directly pushing the platform without any conversion or amplification mechanism, which would drag the first resonance down. The piezoelectric element provides a few microns positioning range but with picometer resolution. Positioners usually include a sensor to achieve closed-loop control. Depending on the displacement range, resonance frequency can be of several kHz.

Which piezo elements can be used for high frequency nanopositioning?

Depending on the required range, positioners can include single actuators or stacks. Multilayer actuators are preferred for their high strain and low operating voltage. Usually a soft-doped ceramic provides good results. At Noliac, we offer the soft-doped ceramic NCE51 for instance.

Read about our NCE51 material at http://www.noliac.com/products/materials/nce51/

Learn about piezoceramic materials in our tutorial at http://www.noliac.com/tutorials/materials/

Sign-up for our free webinar on piezoceramic materials at http://www.noliac.com/tutorials/courses-and-webinars/calendar-and-sign-up/

A multilayer actuator from Noliac for this purpose could be a NAC2012-H06. It provides 6µm of free displacement and an unloaded resonance around 180kHz (free-free). Due to the different boundary conditions and due to the mass of the platform, the first resonance in the application will be lower.

Read more about the piezo actuator NAC2012-H06 at http://www.noliac.com/products/actuators/plate-stacks/show/nac2012-hxx/

More information?

If you want to know more about how Noliac piezo actuators can be used in your high frequency nanopositioning system, please contact us by using our Request for Quote form or contact sale at htt://www.noliac.com/contact