Overview
ISO 10110-12:2019 - "Optics and photonics - Preparation of drawings for optical elements and systems - Part 12: Aspheric surfaces" defines rules for how aspheric surfaces and low-order asymmetric surfaces (cylinders, toroids) are presented on optical drawings. The standard standardizes mathematical descriptions, coordinate systems, and sign conventions used in drawings to ensure unambiguous fabrication and inspection of optical elements. It does not cover off‑axis or discontinuous surfaces (e.g., Fresnel surfaces, gratings) - see ISO 10110-19 for those cases - and it does not prescribe test methods for conformity.
Key topics and technical requirements
- Coordinate system and origin: Right-handed orthogonal system with the Z axis as the optical axis; origin at the vertex of the aspheric surface. Default drawing orientation conventions are specified.
- Sign conventions: Rules for sign of radius of curvature and sagitta (positive when center or sagitta is to the right of the vertex in the defined axis orientation) to avoid ambiguity in drawings.
- Mathematical surface descriptions:
- Rotationally invariant aspheres: conic section + power series (conic constant κ, radius R, aspheric coefficients).
- Orthonormal polynomial descriptions: orthonormal-in-slope and orthonormal-in-amplitude forms (polynomial bases for higher-order departures from base sphere/conic).
- Rotationally variant surfaces: centred quadrics, cylinders, toroids and other low-order symmetric forms.
- Drawing indications: How to specify the theoretical surface, surface form tolerances, centring tolerances, and tolerances for surface imperfections and texture on engineering drawings.
- Scope limitations: Excludes off-axis aspheres and discontinuous surfaces; does not specify inspection/test procedures.
Applications and practical value
- Ensures consistent, unambiguous optical drawings for manufacturing lenses, mirrors, and other aspheric components.
- Used by:
- Optical designers preparing production drawings
- Mechanical drafters integrating optics into assemblies
- Manufacturers and lens shops interpreting aspheric surface specifications
- Metrology and QA labs verifying geometric conformance
- Procurement teams specifying acceptance criteria for optical elements
- Facilitates communication between design, fabrication, and inspection by standardizing notation for conic constants, coefficients, coordinate frames, and tolerances.
Who should use this standard
- Optical engineers, CAD/model authors, optical/mechanical drawing specialists, manufacturing engineers, and quality/inspection personnel in optics and photonics industries involved in design, procurement, fabrication, or metrology of aspheric components.
Related standards
Keywords: ISO 10110-12, aspheric surfaces, optics and photonics, optical drawings, conic constant, coordinate system, sign conventions, surface form tolerances.