What do you need to measure —
which parameter, on which part?
Why this comes first: it is the single most important question. Roughness, flatness, parallelism, step height, layer thickness, form deviation and microstructure geometry lead to different system families. Answering it immediately separates microscope-based systems (small fields, high lateral detail) from large-area systems (form and flatness on bigger parts) — and saves you from evaluating instruments that were never a fit.
Microscope-based, sub-nm Z-resolution
Telecentric, up to 230 × 220 mm with True Stitching
Compact entry system, recipe-based
“Few vendors cover both ends of this table. Polytec builds dedicated micro and macro systems on one platform philosophy — with class-leading fields of view, True Stitching for large areas, and a 4-year warranty across the TopMap family. If your answer sits between two rows, that’s normal: the fit is decided by your part, not by a table.”
How large is your part? Consider Z and XY separately
Why it matters: with larger parts, systems that look identical on paper behave very differently in practice. The trap: "measuring range" figures hide two separate questions — how tall your part can be, and how wide an area you can measure at full quality.
- Tall parts / Z-resolution
Watch out: full resolution along the whole Z-range?
Verify two things: the travel range of the Z-axis, and — the part most datasheets stay quiet about — whether the system delivers its full, constant measurement resolution along that entire range. Some systems only reach their specified resolution within a fraction of the Z-travel. Ask explicitly: "At which Z-positions does your resolution spec apply?"
- Wide parts / stitching quality
Watch out: field of view — and what happens beyond it
If your measurement area is wider than the field of view, the system must stitch multiple fields — and stitching quality is where large-area measurements quietly fail. Good stitching needs a rigid mechanical design and superior software. Ask every vendor to show stitching residuals on a real part, not a demo sample.
Depending on the system, Polytec profilers offer a Z-range of 70 to 100 mm — with full measurement resolution along the entire Z-axis, not just a segment of it.
For wide parts, True Stitching extends the measuring area to 230 × 220 mm and beyond with documented, audit-ready residuals. In an independent comparison at one of Germany's top technical universities, the stitching results of five known manufacturers were evaluated side by side — the institute was convinced by True Stitching and purchased the Polytec system.
What resolution and tolerances do you need — and why datasheets will mislead you
Upfront and in full transparency: our systems deliver top-tier resolution and repeatability, and we can quote impressive numbers with the best of them. But that is not why this checkpoint exists.
The trap: resolution comparison is the classic failure point of optical metrology purchasing. The typical approach — collect datasheets, build a comparison table — fails because every manufacturer defines their own measurement conditions for the values they publish. Two "0.1 nm" claims can describe entirely different real-world performance. Two recommendations:
Ask for the fair data sheet
Request specifications according to standardized, harmonized measurement conditions (a “fair data sheet”). Values determined under defined, comparable conditions give you a far more stable basis for comparison than marketing numbers. Any vendor confident in their instrument will provide them — hesitation is a data point too.
Test the system — don’t read about it
The resolution and repeatability you will actually achieve depends on your parts, your environment and your operators. The only reliable proof: a feasibility study on your own samples, or better yet, renting the system and running it with your team, in your environment, across your range of parts — before any purchase decision.
“We offer both, deliberately: a free feasibility study — you send parts, our application engineers measure them and you receive the full data — and rental systems (PolyRent) that prove themselves in your own process. We’d rather win on your measurement results than on a datasheet.”
Who will operate it and where?
Usability and automation
Why it matters: a system that only a metrology specialist can operate becomes a bottleneck the day it moves near production. Before comparing instruments, be honest about the environment (climate-controlled lab, at-line, shop floor?) and the operators (metrology engineers, or trained production staff?).
- Usability
Watch out: expert instrument or push-button workflow?
Check whether recurring measurements can be stored as recipes and started by non-specialists with a single action — including automatic evaluation and pass/fail output. Ask for a live demo where your colleague, not the vendor's application engineer, runs the measurement.
- Automation & environment
Watch out: lab instrument in disguise?
Many optical profilers are laboratory instruments that struggle with vibration and temperature on a shop floor. If production use is on your roadmap — even years out — check robustness and automation interfaces (MES/PLC) now. Retrofitting is expensive; replacing is worse.
Polytec systems are built for production, not just the lab: rugged design with few moving parts, Environmental Compensation against vibration, and MES/PLC interfaces for integration. Our new Sherpa software guides operators through recipe-based measurements — from single-button workflows for production staff to full analytical depth for metrology experts.
And the platform is modular: start at-line, grow toward in-line without replacing the system.
Why buyers shortlist Polytec — the summary
Largest field of view
More surface per measurement — often several parts per shot on a tray.
True Stitching
Large-area measurement with documented residuals — verified in independent university comparison.
Micro and Macro systems
One vendor covering microscope-scale detail and large-area form measurement.
Full resolution over full Z-range
70–100 mm Z-travel with constant measurement resolution along the entire axis.
Sherpa software
Recipe-based operation for production staff, analytical depth for experts.
4-year warranty
Plus feasibility studies and rental systems — invest after the proof, not before.
Three system families cover the full range — from sub-nanometer research to high-throughput inspection on the shop floor. Not sure? Request the feasibility study and we'll recommend a setup based on your actual parts.
Micro Profiler
Microscope-based WLI for microstructures, MEMS, precision optics and tribology.
Field of view: 0.07–3.7 mm² · Z-resolution: sub-nm
Macro Profiler
Telecentric large-area profiling for flatness, parallelism, step height and form — even inside bores.
Single FoV: 44 × 33 mm · with True Stitching: 230 × 220 mm+ · up to 2M points in seconds
Roughness Tester
Compact, cost-effective system to move from tactile stylus to areal optical roughness measurement.
Field of view: 0.07–3.7 mm · areal, non-contact · recipe-based operation
