ISO 25178-603:2013

Overview

ISO 25178-603:2013 specifies the metrological characteristics of non-contact phase‑shifting interferometric (PSI) microscopes used for areal surface texture and surface topography measurement. As part of the ISO 25178 GPS (Geometrical Product Specification) family, this part defines terms, measurement quantities and influence factors specific to PSI profile and areal microscopes, and includes informative annexes on components, theory of operation, errors and corrections, and the GPS matrix model.

Key Topics

• Scope and terminology
  • Definitions related to areal surface texture measurement, coordinate systems, measurement loop and real / electromagnetic surface concepts.
  • PSI‑specific terms and measurement vocabulary used consistently across areal metrology.
• Metrological characteristics
  • Description of influence quantities affecting PSI measurements (optical properties, scanning systems, environmental and instrumental factors).
  • Response curve and amplification coefficients for x, y and z axes and the treatment of linearity deviations.
  • Definitions of instrument noise, measurement noise, and surface topography repeatability as metrics for assessing precision.
• Sampling and resolution
  • Concepts of sampling interval (Dx, Dy), digitization step (Dz), lateral resolution (Rl), width limit for full height transmission (Wl) and lateral period limit (DLIM) - parameters that influence the ability to detect and accurately measure surface features.
• Informative guidance
  • Annex A: Components of a PSI microscope.
  • Annex B: Theory of operation for phase‑shifting interferometry.
  • Annex C: Errors and corrections for PSI microscopes.
  • Annex D: Relation to the GPS matrix model.

Applications and Users

ISO 25178-603 is intended for organizations and professionals who design, use, validate or specify non‑contact areal surface metrology systems:

• Metrology and calibration laboratories assessing instrument performance and measurement uncertainty.
• Instrument manufacturers developing PSI microscopes and documenting nominal instrument characteristics.
• Quality engineers and R&D teams in precision manufacturing, optics, semiconductors, medical devices and automotive sectors who require repeatable areal surface texture data.
• Standards developers and auditors aligning specifications across the ISO 25178 GPS chain.

Practical benefits include clearer instrument specifications, consistent interpretation of areal measurement parameters, and guidance on how instrument design and operating choices (sampling, optics, environmental control) affect measurement fidelity.

Related Standards

• ISO 25178 series (areal surface texture), including Parts 1, 2, 3, 6, 601–606 and calibration parts (701–703).
• ISO/TR 14638 (ISO/GPS Masterplan) and ISO 8015 (fundamental GPS rules) for context and decision rules.

Keywords: ISO 25178-603, phase‑shifting interferometry, PSI microscopy, areal surface texture, surface topography, non‑contact instruments, metrological characteristics.