Contact person
Mikolaj Malinowski
Forsknings-och utvecklingsingenjör
Contact Mikolaj
High Resolution Surface Topography measurement
Paper surface roughness plays a crucial role for printability and visual appearance. Several types of instruments are available topography measurements of paper surfaces in different degrees of detail. The FRT MicroProf instrument has the advantage of combining high resolution with a large scanning area. Many other materials can be analyzed as well
Purpose
Surface defects can be quantified in a very detailed way
Surface classification of different samples can be made.
Method
The instrument uses a fast non-contacting high-resolution sensor, based on confocal microscopy with chromatic aberration. When white light passes through a lens with chromatic aberration, different colors focus at different distances. The color composition of the reflected light is analyzed and translated into a height position.
A surface is analyzed by moving the sample holder (X-Y vacuum table), while the sensor is in a fixed position. The utilization of a fixed sensor head means an advantage in speed, when compared to instruments using for example a z-scanning confocal focus sensor.
The x/y resolution is from 2x2 µm and the z-resolution 3 nm.
Deliveries
The height data is evaluated to generate height maps, profiles and pictures as well as common surface parameters, e.g. Ra, Rs etc., depending on the customer's needs.
A useful way of evaluating roughness is to band-pass filter the height map using the image analysis technique Fast Fourier transform (FFT) to divide the height variation in spatial size classes to get roughness components in different wavelength bands.
Resultat in form of Excel- and Wordfiles.
