Fast steps with nanometer precision

Piezo stepping drives from Physik Instrumente (PI) can be combined with a high-resolution linear encoder for nanometer accuracy over the complete scanning range – and are now also available for PIFOC focusing systems for microscope objectives.

The focal plane can easily be changed with a single mechanism thanks to the combination of high resolution and long travel ranges. There is therefore often no need for a combined Z-positioning of the objective, e.g. with stepper motor and additional piezo stages.

Piezo stepping drive – the multi-talented linear piezomotor

The NEXACT® piezo stepping drive advantageously combines the best characteristics of piezomotor principles in a compact unit: High resolution, high force and high speed. The feed motion is achieved solely via the nanometer-accurate motion of clamped piezo actuators – non-wearing, high resolution and with controllable speed.

In stepping mode, high positional resolution can be achieved over the complete travel range at high drive forces. Moreover, the high stiffness also allows a rapid oscillatory motion with an amplitude of 7 micrometers and resolutions of up to 30 pm (analog operation, open-loop).

In addition, the drive is self-locking when it has reached its target and no longer needs to be powered, which is why it does not heat up. The position is stable in the nanometer range so there is no jitter about the target position, as is the case with servo motors and stepper motors.