PI invented fast focusing stages with nanometer resolution more than 30 years ago. Its PIFOC® product family spans hundreds of standard and custom products, optimized for tasks including surface metrology in semiconductor applications, super-resolution microscopy, slide scanning, genome sequencing, and magnetic tweezers.
A new, long-travel linear slide is now available with a voice coil linear motor to complement the piezo-flexure and piezo motor-based units. Piezo drives are very compact and can be easily integrated in positioning devices that mount on a microscope turret, however their travel range is typically less than one millimeter – on the upside, they can achieve sub-nanometer precision and sub-millisecond settling times.
For fast focusing applications where a traditional microscope is not required and/or longer travel ranges of several millimeters are essential, the new V-308 nanopositioning slide with electromagnetic direct drive provides a solid solution.
At the core of the V-308 nanofocus system is a single axis slide guided laterally by high-precision crossed roller bearings. The slide is driven by a centrally mounted linear voice-coil motor, specifically developed by PI for high dynamics, fast settling, and high resolution. Acceleration to 0.8g and velocity to 8”/sec are feasible, while extremely short step-and-settle times <15msec (step size to 1/4µm) within an error band of only ±15 nanometers can be achieved. The closed-loop linear slide integrates PI’s proprietary PIOne ultra-high resolution optical incremental encoder, providing sub-nanometer resolution feedback, based on an interferometric-type read head. When operated with a PI motion controller, the low friction V-308 linear slide can perform repeatable minimum incremental motion steps of 10 nanometers (see graph) and bidirectional repeatability of 25 nanometers.