Overview
ISO 15253:2021 - "Ophthalmic optics and instruments - Optical and electro‑optical devices for enhancing low vision" - defines requirements and test methods for low vision devices specified by manufacturers for use by visually impaired persons. The standard covers both optical aids (lenses, prisms, mirrors, magnifiers) and electro‑optical systems (camera + display/video magnifiers/CCTV/head‑mounted displays). Implantable low vision devices are excluded. ISO 15253:2021 merges and updates previous ISO 15253 and ISO 15254 editions and adds requirements for filters and tints, image relocation, and text‑to‑speech features.
Key topics and requirements
- Scope & classification: Distinguishes optical vs electro‑optical devices and defines terms (e.g., low vision device, filter, neutral density filter).
- General manufacturer requirements: Risk assessment and management (aligned with ISO 14971 principles), materials, dimensions and weight, flammability/ignitability, resistance to perspiration, robustness and drop resistance.
- Optical device requirements:
- Spatial resolution and equivalent power (for near/intermediate devices)
- Magnification metrics (angular, transverse)
- Exit image distance (stand magnifiers) and entrance pupil diameter (telescopes)
- Transmittance, filters/tints, and image relocation (prisms or mirrors)
- Electro‑optical device requirements:
- Display size and image characteristics, display magnification and uniformity
- Ambient temperature range, working distance, object (XY) table functionality
- Text‑to‑speech capability and electrical safety requirements (referencing IEC/IEC‑medical series)
- Test methods: Procedures for measuring spatial resolution, magnification, lateral variation of magnification, exit image distance, display magnification and uniformity.
- Manufacturer information: Marking, labelling and instructions for use required to accompany devices.
Applications and users
- Who uses the standard: Manufacturers and designers of low vision aids, test laboratories, conformity assessors, procurement specialists in healthcare and rehabilitation, clinicians and low vision specialists advising device selection.
- Practical value:
- Ensures consistent performance metrics (e.g., magnification, resolution, transmittance).
- Guides product safety (flammability, perspiration resistance, electrical safety) and usability (image relocation, text‑to‑speech).
- Supports regulatory compliance and product documentation for clinical and consumer markets.
Related standards
Relevant normative references cited in ISO 15253:2021 include: ISO 12312‑1, ISO 12870, ISO 14889, ISO 14971, ISO 15004‑1/2, IEC 60601‑1 series and IEC 60695‑2‑11. These inform eye/face protection, spectacle frames/lenses, medical device risk management and electrical safety testing.
Keywords: ISO 15253, low vision devices, optical and electro‑optical devices, test methods, magnification, spatial resolution, filters and tints, image relocation, text to speech, manufacturer requirements.