ISO 16610


ISO 16610: Geometrical product specifications – Filtration is a standard series on filters for surface texture, and provides guidance on the use of these filters in various applications.
Filters are used in surface texture in order reduce the bandwidth of analysis in order to obtain functional correlation with physical phenomena such as friction, wear, adhesion, etc. For example, filters are used to separate roughness and waviness from the primary profile, or to create a multiscale decomposition in order to identify the scale at which a phenomenon occurs.
Historically, the first roughness measuring instruments - stylus profilometer - used to have electronic filters made of capacitors and resistors that filtered out low frequencies in order to retain frequencies that represent roughness. Later, digital filters replaced analog filters and international standards such as ISO 11562 for the Gaussian filter were published.

Filter toolbox for surface texture

Today, a full set of filters is described in the ISO 16610 standard series. This standard is part of the GPS standards on Geometrical Product Specification and Verification, developed by ISO TC 213.

Filter matrix

ISO 16610 is composed of two families of documents, one for profiles and one for surfaces. A general introduction is provided in:
Profile filters are defined for open profiles, measured along a line by profilometers and expressed as z=f, as well as for closed profiles, measured around a circular component by roundness instruments and expressed as radius=f. Most of these standards were first published as a Technical Specification and later converted to International Standards or withdrawn.
Parts related to profile filters are:
Note: ISO/TS 16610-32 on robust spline filters was published as a technical specification in 2009 but was withdrawn in 2015 as it provides very similar results as the Robust Gaussian regression filter while being much more complex.

Areal filters

Areal filters are defined for surfaces measured either by lateral scanning instruments or optical profilometers.
Parts related to areal filters are:
The following section describes which application is suitable for each filter. References to published papers or books are provided when available. Readers are encouraged to add below proven applications related to surface texture and tribology where a particular filter can be used alone or in conjunction with other treatments or analyses to provide significant results.
; Part 21 - Profile Gaussian filter
; Part 22 - Profile Spline filter
; Part 29 - Profile Spline wavelets
; Part 31 - Profile Robust Gaussian filter
; Part 41 - Profile Morphological filter
; Part 45 - Profile Segmentation filter
; Part 49 - Profile Scale space technique
; Part 61 - Areal Gaussian filter
; Part 62 - Areal Spline filter
; Part 71 - Areal Robust regression Gaussian filter
; Part 81 - Areal Morphological filter
; Part 85 - Areal Segmentation filter
; Part 89 - Areal Scale space technique