Overview
ISO/TR 20278:2015 is a Technical Report that summarizes existing knowledge and guidance on unwanted reflections from the active and inactive areas of display surfaces visible during use. It focuses on the ergonomics of display glare - both direct glare and glare by reflection - and explains how unwanted reflections can cause visual discomfort (asthenopia), disability glare, and reduced task performance. The report is intended as a knowledge base that may inform future updates to the normative requirements in the ISO 9241 series.
Key Topics
- Definitions and concepts: glare, discomfort glare, disability glare, direct glare, glare by reflection, veiling glare, gloss and specular gloss.
- Measurement tools: use of glossmeters and reflectometers to quantify surface reflectance and specular components.
- Interaction of reflection components: how specular, diffuse and haze reflections combine and affect perceived glare.
- Luminance balance and ambient lighting: role of ambient illuminance, workstation arrangement and lighting design in reducing reflections.
- Active vs inactive areas: literature review on reflections from the screen (active area) and bezel, housing or other inactive areas visible during use.
- Human factors: links between reflections and visual symptoms (asthenopia), accommodative and vergence stress from reflected images.
- Guidance for specifications: practical considerations for specifying unwanted reflections in product requirements (non‑normative).
Practical Applications
ISO/TR 20278:2015 is useful for anyone involved in designing, specifying or evaluating electronic displays and work environments:
- Display manufacturers - to guide surface finish, bezel design and reflectance control.
- Ergonomists and occupational-health professionals - to assess risk of visual discomfort and recommend workstation lighting/layout.
- Lighting and facility designers - to balance ambient illumination and reduce disturbing reflections.
- Procurement and quality teams - to define acceptance criteria for reflections and glare in tender documents.
- User-interface and product designers - to understand how inactive area reflections can distract or reduce readability.
Related Standards
- ISO 9241 (ergonomics of human–system interaction) - contains normative requirements related to unwanted reflections and is the primary standards series referenced by this Technical Report.
- National and regional workplace lighting regulations (e.g., EN standards) are also relevant for specifying ambient illuminance and glare controls.
ISO/TR 20278:2015 provides a practical, evidence-based foundation for reducing unwanted reflections on display surfaces, improving visual comfort and informing standards development and product specifications.