The new N-725 PIFOC scanner for microscope objectives with NEXACT piezo stepping drives provides travel ranges of up to one millimeter along the optical axis. At the same time the technology allows rapid positioning: The N-725 focusing system achieves transient times of around 20 milliseconds for steps of 200 nanometers. It has an extremely compact design and is no larger than conventional, piezobased PIFOC objective stages.
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 Zpositioning of the objective, e.g. with stepper motor and additional piezo stages.
Piezo stepping drive - the multitalented 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 nanometeraccurate motion of clamped piezo actuators - nonwearing, 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, openloop).
In addition, the drive is selflocking 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.