Auniontech APA Series Amplified Piezoelectric Actuators

Overview

The Auniontech APA Series Amplified Piezoelectric Actuators are high-precision, preloaded electromechanical transducers engineered for sub-nanometer resolution motion control in demanding metrology and photonics applications. Based on the principle of inverse piezoelectric effect—where applied voltage induces controlled lattice strain in ferroelectric ceramics—the APA actuators integrate a monolithic flexure amplification mechanism to overcome the inherent limitation of small native stroke in standard piezoceramic stacks. Unlike conventional lever or hydraulic amplifiers, the flexure-based architecture achieves mechanical gain through elastic deformation of precision-etched silicon or stainless-steel compliant structures, eliminating backlash, friction, wear, and stick-slip phenomena. This results in true hysteresis-free operation, exceptional repeatability (<0.05% of full scale), and long-term stability under continuous cycling—critical attributes for closed-loop displacement sensing in geometric metrology systems, interferometric stage calibration, and dynamic optical path length control.

Key Features

• Monolithic flexure-guided design ensures zero mechanical play, no lubrication requirements, and immunity to particulate contamination—ideal for cleanroom-compatible metrology environments.
• Preloaded configuration maintains consistent compressive bias across the piezoceramic stack, preventing tensile stress-induced cracking and enabling bidirectional voltage control without performance degradation.
• Hysteresis-free response with <0.2% nonlinearity (typ.) over full stroke, validated per ISO 10360-2 and VDI/VDE 2634 Part 2 standards for displacement sensor characterization.
• High resonant frequency (up to 2.1 kHz for APA-40U) supports dynamic positioning tasks such as adaptive optics wavefront correction and high-speed focus scanning in confocal microscopy.
• Integrated strain gauge or capacitive feedback options available for closed-loop operation, compliant with ISO/IEC 17025 traceability requirements when paired with calibrated readout electronics.
• RoHS-compliant construction with hermetically sealed ceramic housing; operating temperature range: –20 °C to +70 °C (non-condensing).

Sample Compatibility & Compliance

The APA series is designed for integration into precision geometric measurement instruments—including laser interferometers, coordinate measuring machine (CMM) probe modules, and nano-coordinate metrology platforms—where sub-micron spatial fidelity and thermal drift minimization are mandatory. All models comply with CE marking directives (EMC 2014/30/EU, LVD 2014/35/EU) and meet IEC 61000-6-2/6-4 immunity and emission thresholds. Mechanical interface specifications conform to DIN 476-1 (metric mounting threads) and ISO 8000-101 (geometric product specification). For regulated laboratory environments, the APA’s deterministic displacement behavior supports GLP-compliant validation protocols, and firmware-enabled audit trails (when used with compatible controllers) align with FDA 21 CFR Part 11 data integrity expectations for QC/QA instrumentation.

Software & Data Management

Auniontech provides the APA Control Suite—a cross-platform (Windows/Linux/macOS) application programming interface (API) supporting LabVIEW, MATLAB, Python (PyVISA), and C/C++ development environments. The suite enables real-time waveform generation (sine, sawtooth, arbitrary), closed-loop PID tuning with auto-identification of plant dynamics, and synchronized multi-axis trajectory planning. Raw displacement data is exported in HDF5 format with embedded metadata (timestamp, voltage setpoint, ambient temperature, serial number), ensuring FAIR (Findable, Accessible, Interoperable, Reusable) data principles. Controller firmware supports IEEE 1588 Precision Time Protocol (PTP) for time-stamped synchronization across distributed metrology nodes—essential for multi-sensor fusion in advanced coordinate measurement systems.

Applications

• Nanoscale focusing in super-resolution fluorescence microscopy (e.g., STED, PALM) requiring <5 nm step resolution and <10 ms settling time.
• Active vibration cancellation in optical interferometry setups, where APA-40U’s 250 N blocking force stabilizes mirror mounts against seismic and acoustic disturbances.
• Dynamic beam steering in free-space optical interconnects, leveraging APA-33U’s high stiffness (2.2 N/µm) and low phase lag for kHz-range angular modulation.
• Probe tip actuation in scanning white-light interferometers (SWLI) and atomic force microscope (AFM) heads, where repeatable 33–220 µm linear displacement enables Z-axis scanning without gear-driven mechanisms.
• Calibration artifact positioning in primary standards laboratories, where traceable displacement generation supports ISO/IEC 17025 accreditation for length measurement uncertainty budgets.

FAQ

What distinguishes amplified piezoelectric actuators from standard piezostacks?
Amplified designs use passive elastic mechanisms—such as flexure hinges or bimorph levers—to multiply the native strain of piezoceramics (typically ~0.1–0.2%), achieving strokes up to 220 µm while preserving linearity and bandwidth.
Can APA actuators operate in vacuum environments?
Yes—models with metal-ceramic hermetic seals and outgassing-tested adhesives are rated for UHV conditions (<10⁻⁷ mbar); optional bake-out support to 120 °C is available upon request.
Is closed-loop operation supported natively?
The APA series is open-loop by default but fully compatible with external capacitive or strain-gauge position sensors; Auniontech offers integrated feedback variants (APA-C series) with factory-calibrated transfer functions and NIST-traceable certificates.
How is thermal drift compensated during extended metrology runs?
Built-in temperature sensors enable feedforward compensation in controller firmware; combined with low-power drive electronics (max. 1.2 W static dissipation), thermal displacement remains below ±2 nm/°C over the operational range.
What mounting interfaces are standardized?
All APA models feature M6 threaded holes on base and top surfaces, conforming to ISO 2768-mK general tolerances; custom kinematic mounts and Ø25 mm optical post adapters are available as accessories.