Developing Areal Surface Texture Measuring Standards

Olympus has announced that the National Physical Laboratory (NPL) is using its LEXT OLS4000 in a project to establish good practice guidelines for the calibration of 3D/areal surface texture measuring instruments.

Instruments capable of providing areal surface texture information, such as the Olympus LEXT OLS4000 confocal microscope, are becoming increasingly popular, but currently lack any traceability routes. As a result, ISO standards are being prepared by a team led by Prof Richard Leach, Principal Research Scientist at the NPL.

As an important component of these standards, Professor Leach’s team is defining good practice guidelines using archetypal examples of: stylus instruments; white light interferometers; focus variation
instruments; and confocal microscopes.

The project will use a range of artefacts to characterise the scaling, linearity, orthogonality, angular response, repeatability and resolution of the X, Y and Z axes. The LEXT OLS4000 is being used by Prof
Leach’s team as the archetypical confocal instrument, although the guide will not be specific to the Olympus instrument.

As well as enabling the generation of good practice guides, the project will also define the reference areal artefacts to be used during calibration. Once the project is complete, users of areal surface
measurement instruments will be able to obtain a calibration ‘bento’ box with the guidelines and artefacts to ensure better accuracy both within and between instruments and projects.