ISO 25178-602:2010

Overview

ISO 25178-602:2010 is part of the ISO 25178 series on Geometrical Product Specifications (GPS) for areal surface texture. This part defines the nominal design and metrological characteristics of a particular class of non-contact surface texture instruments - optical profilers that use a confocal chromatic probe based on axial chromatic dispersion of white light. The standard describes instrument composition (optoelectronic controller, fibre optic link and chromatic objective), measurement geometry and the terminology required to specify and evaluate these instruments for areal surface texture measurement.

Key Topics

• Instrument concept and scope
  • Confocal chromatic probe principle (axial chromatic dispersion) and typical configurations (point, line, field sensors).
  • Main components: optoelectronic controller, linking fibre optic cable and chromatic objective.
• Metrological characteristics
  • Definitions and classification of measurement errors (measurement error, systematic and random), corrections and residual correction error.
  • Description of the measurement loop (workpiece → probe → drive units → measuring stand) and influence on measurement uncertainty.
• Coordinate and scanning system
  • Instrument coordinate system (X, Y, Z), lateral scanning system, drive units X and Y, and lateral position sensors.
• Optical parameters
  • Concepts such as angular (half) aperture, numerical aperture and wavelength-dependent behavior of chromatic objectives.
• Annexes and guidance
  • Normative and informative annexes provide configuration classification (Annex A), detailed principles of chromatic confocal imaging (Annex B), concept diagrams (Annex C) and relation to the GPS matrix (Annex D).

Applications and Users

ISO 25178-602:2010 is intended for organizations and professionals involved in surface metrology and instrument specification:

• Instrument manufacturers designing confocal chromatic probe profilers.
• Calibration and test laboratories establishing acceptance/reverification procedures and uncertainty budgets.
• Metrologists, quality engineers and R&D teams selecting measurement systems for areal texture analysis.
• Industries requiring non-contact areal surface measurement - e.g., precision optics, medical devices, automotive, aerospace, semiconductor and surface finishing processes.

Practical benefits include reliable specification of instrument performance for delicate/soft surfaces, high-resolution areal topography, and options for both areal and profile measurements.

Related standards

ISO 25178-602 is part of the ISO 25178 family and references other GPS documents such as:

• ISO 25178-2 (terms & parameters),
• ISO 25178-6 / -7 (method classification & software),
• ISO 3274, ISO 4287 and ISO 10360-1 for related profile and CMM vocabulary and test methods.

Keywords: ISO 25178-602:2010, confocal chromatic probe, areal surface texture, axial chromatic dispersion, non-contact instrument, optical profiler, surface metrology.