Overview
ISO 10110-6:2025 - Optics and photonics - Preparation of drawings for optical elements and systems - Part 6: Centring and tilt tolerances - defines how to indicate centring and tilt tolerances on optical drawings. It is part of the ISO 10110 series that standardizes drawing indications for optical elements, subassemblies and assemblies. The 2025 third edition expands scope to include tilt tolerances and clarifies datum definitions (including a circular datum) and datum systems used to reference optical surfaces.
Key topics and technical requirements
- Scope of application: rules apply to plano, rotationally invariant (spherical/aspherical), circular and non‑circular cylindrical (cylindrical/acylindrical) and general (non‑symmetrical) surfaces-general surfaces referenced to ISO 10110‑19.
- Datums and datum features: definitions and conventions for datum features (real physical features), datums (theoretical references), datum axes, datum systems and common datums; guidance on when datums must be shown on drawings.
- Centring and tilt definitions: how to specify tilt angles for spherical, aspheric, cylindrical and non‑cylindrical surfaces; lateral displacement definitions for aspheres; multiple tilt angles for cylindrical surfaces.
- Drawing indications: standardized notation and placement for centring/tilt tolerances, including datum order conventions and examples illustrating acceptable indications.
- Special cases: provisions for cement wedges in cemented assemblies, surfaces without optical function (mechanical faces), field stops, reticles and other patterned surfaces.
- Annex A (informative): practical guidance on selecting datums, datum features and datum systems for optical components and assemblies.
- Normative references: links to ISO 1101 (geometrical tolerancing) and ISO 10110‑1 (general).
Note: ISO 10110‑6:2025 does not mandate specific numeric tolerances; it standardizes how tolerances are expressed on drawings.
Practical applications - who uses it and why
- Optical designers and systems engineers: to document how elements must be positioned and aligned within optical assemblies.
- Mechanical engineers and opto‑mechanical designers: to link optical datums to mounting features (edge cylinder datums, bores).
- Manufacturers and precision optics shops: to interpret drawing tolerances for fabrication and assembly.
- Metrology and QA labs: to verify centring and tilt against a standardized datum system and produce acceptance reports.
- Procurement/spec writers: to create clear, unambiguous drawings for suppliers, reducing errors and rework.
Practical benefits include reduced alignment risk, consistent inspection criteria, improved supplier communication and compatibility across international projects.
Related standards
- ISO 10110 series (general drawing rules for optics)
- ISO 10110‑1 (General)
- ISO 10110‑19 (General surfaces description)
- ISO 1101 (Geometrical product specifications - tolerancing of form, orientation, location and run‑out)
Keywords: ISO 10110-6:2025, centring and tilt tolerances, optical drawings, datum axis, datum feature, optical tolerancing, optics and photonics.