Meaning
Non-contact surface measurement methods provide three-dimensional analyses of polymer and tool surface topographies. By defining areal parameters rather than single-line profiles, iso 25178 optical profilometry enables the characterisation of complex textured surfaces. This standard governs the use of optical instruments like coherence scanning interferometers and confocal microscopes to capture surface heights without touching the specimen.
It is widely used to verify the finish of injection moulds and the resulting plastic parts. Because no physical probe contacts the specimen, the method prevents the deformation of soft polymer microstructures during measurement.
Surface Measurement
Optical systems capture height variations across a defined area to build a high-resolution map of the part surface. In the execution of iso 25178 optical profilometry, the instrument projects light onto the sample and analyzes the reflected wavefronts. This allows the metrology system to detect sub-nanometre variations without damaging soft polymer surfaces.
Texture Parameter
Areal parameters provide a complete description of the surface compared to traditional linear metrics. The measurements yield values for root-mean-square height and peak-to-valley distance across the entire sample area. These statistics give moulders a clearer picture of how well a cavity finish replicates onto the moulded plastic.
Inspection Value
In high-performance moulding, this technique helps to audit mould wear over long production runs. A tool that produces high-frequency waveguide components must maintain a surface roughness below a specific threshold. Regular profiling runs detect micro-abrasions in the steel before the moulded parts suffer from excessive signal attenuation.
