Laser interferometry is a particularly useful analysis, allowing for non-destructive high resolution imaging and surface topography mapping that is suitable for a wide range of samples. With scan areas up to 10cm x 10cm, surface resolutions down to 1µm, a maximum depth of field of 24mm and an axial resolution as low as 0.008µm the imaging capabilities are versatile and comprehensive. Laser interferometry offers an alternative high resolution imaging technique to those that require extensive preparation, alteration or partial destruction of the sample.
In addition to imaging, the SolarMap software allows for a variety of analyses including:
- Pit and peak depth, width and volume measurement;
- 2D line parameter values conforming to standards ISO 4287, ISO 12780, ISO 12181 and ASME B46.1;
- 3D surface parameter values conforming to standards ISO 25178, EUR 15178N, ISO 12781 and ASME B46.1;
- Surface area at depth/height measurement; Abbott-Firestone Curve and/or histogram of pit depth distribution; and
- Roughness and waviness extraction and form removal capabilities allowing for scans of cylindrical or spherical surfaces.
Some examples of our previous work include pit depth analysis of steel and aluminium coupons for corrosion testing, relative surface area of pits for rolled steel intrusion monitoring, and electrical insulator surface wear profiling.
The Solarius SolarScan AOP150 laser interferometer creates height profile line scans by interpolating data points measured at set intervals. The sample is placed atop a high precision stage that can support weights of up to 12kg. The stage then sweeps out the line scan by passing the sample below an optical pen emitting a low-power laser. The laser is reflected off the surface of the sample and the height of the sample is recorded by measuring the constructive and destructive interference in the reflected laser beam. In addition to line scan profiles, surface scans can be produced by combining line profiles (also by data point interpolation) to create 3D surface profiles.
