Precision motion control specialist Physik Instrumente (PI) provides new options for objective focusing stage applications. High-speed and high-resolution focusing is critical in wafer inspecting, measuring optical components or imaging biological samples. Modern microscopes and surface metrology systems routinely operate at magnifications where depth of focus shrinks to just a few micrometers — or less. Under these conditions, even minor variations in sample height, surface topography, thermal drift or vibration can push the area of interest out of focus, degrading both image quality and measurement accuracy.
Two nano-positioning drive technologies, one goal
PI addresses this challenge with fast nano-precision focusing systems built around two complementary drive technologies. The piezo-driven P-725 and voice-coil-driven V-308 objective focusing stages can quickly adjust the objective lens position with nanometer-level resolution and millisecond response times, keeping systems locked on target regardless of throughput demands or environmental disturbances.
In optical profilometry and 3D surface metrology, rapid focus scanning enables accurate reconstruction of complex surface features. In automated microscopy, it allows large areas or multiple samples to be inspected at high throughput without sacrificing image sharpness.
PI objective focusing stages: voice coil (left) for long travel to 7mm; piezo (right) for compact size and fast response with travel ranges to 800µm. Source: PI
Semiconductor inspection: Where speed and precision converge
The demands are particularly stringent in semiconductor inspection, where millions of features must be measured quickly and accurately. Precision objective focusing stages that minimize focus error and reduce settling times directly improve throughput, enhance repeatability and enable reliable detection of ever-smaller defects and structures. As imaging resolution continues to advance and production volumes grow, fast nano-positioning focus systems have become a critical enabling technology for next-generation metrology and inspection equipment.
Advanced control: The other half of the equation
Achieving nanometer precision in milliseconds requires more than precision mechanics and high-quality sensors — it demands advanced electronics and control algorithms to match. PI offers both benchtop and OEM digital motion controllers with built-in linearization and optimization routines tailored for scanning and fast step-and-settle applications, ensuring that mechanical performance is fully realized in real-world operating conditions.
Industries served and applications
Industries and applications served include:
- Semiconductor inspection
- Metrology
- DNA sequencing
- Microscopy
- Photonics
- Laser processing
