Overview
ISO 10940:2009 - "Ophthalmic instruments - Fundus cameras" specifies requirements and type test methods for fundus cameras used to observe, photograph or record electronic images of the human fundus for diagnosis. It is intended for non‑contact fundus cameras (excluding contact instruments and scanning‑laser devices) and takes precedence over ISO 15004‑1 and ISO 15004‑2 where differences exist. The standard addresses optical performance, construction, optical radiation (light) hazard, test setups and required accompanying documentation.
Key Topics
- Optical properties and resolving power
- Minimum resolving power requirements depend on angular field of view (FOV). For FOV ≤ 30°: centre ≥ 80 lp/mm, mid‑field ≥ 60 lp/mm, periphery ≥ 40 lp/mm. For FOV > 30°: centre ≥ 60 lp/mm, mid‑field ≥ 40 lp/mm, periphery ≥ 25 lp/mm.
- When using near‑infrared (NIR) imaging, resolving‑power limits are reduced by a factor of 1.6.
- Field of view, magnification and pixel pitch
- Angular FOV tolerance: ±5%.
- Magnification tolerance: ±7% (film recording).
- Pixel‑pitch tolerance on the fundus: ±7% (digital sensors).
- Optical and mechanical design
- Instruments must minimize reflections and stray light; high‑eye‑point eyepieces must provide ≥ 17 mm clearance.
- Dioptre and focus adjustment ranges are specified (e.g., focus compensation −15 D to +15 D).
- Optical radiation hazard
- Classification and limits follow ISO 15004‑2 (group 1 or group 2 instruments); combined/source emissions and cumulative pulsed/continuous exposures are covered. Annex A gives guidance on hazard measurement and Annex B on safe use.
- Test methods
- Type tests use a standardized test target at 1 m from the entrance pupil with defined illumination band‑pass (520–560 nm for visible, 790–890 nm for NIR).
- Procedures are defined for verifying resolving power, FOV, magnification and pixel pitch.
- Documentation
- Required user manual content includes manufacturer details, transport conformity, compliance claims (reference to ISO 10940:2009), resolving‑power information, image artefacts, magnification/pixel‑pitch data.
Applications
ISO 10940:2009 is directly applicable to:
- Fundus camera manufacturers for product design, verification and CE/market claims.
- Test laboratories and quality departments performing type tests and acceptance testing.
- Regulatory reviewers and procurement officers assessing device compliance and image‑quality specifications.
- Clinical engineers and biomedical equipment maintainers validating imaging performance.
Related Standards
Keywords: ISO 10940:2009, fundus cameras, ophthalmic instruments, resolving power, field of view, pixel pitch, optical radiation hazard, test methods, ISO 15004, IEC 60601.