Overview
ISO/TR 9241-312:2020 - "Ergonomics of human-system interaction - Part 312: Readability of electrophoretic displays" is a Technical Report from ISO that surveys recent research on the readability of electrophoretic (e-paper) displays. It explains how to evaluate readability and how to define the context of use for reflective displays commonly found in e‑readers and other low‑power, reflective devices.
This document is part of the ISO 9241‑300 series (visual ergonomics) and focuses on the human factors and visual performance aspects that affect reading on electrophoretic displays.
Key topics and requirements
The report organizes findings and practical evaluation guidance, including:
- Literature review: summaries of recent work on readability and legibility for electronic paper displays.
- Readability vs legibility: distinctions and relevance for EPD (electrophoretic display) design and testing.
- Evaluation under varied illumination: experimental approaches for assessing readability across multiple illumination levels (the report includes methods and results for 14 illumination conditions).
- Experimental conditions & methods: guidance on setting up evaluations - equipment, participant selection, illumination conditions, and task/evaluation methods (e.g., performance tasks and subjective scales).
- Visual Analogue Scale (VAS): using VAS as a baseline subjective measure for readability.
- Minimum illuminance verification: approaches to determine the lowest ambient light needed for acceptable readability on EPDs.
- Character size and contrast: analysis of how font size and contrast ratio influence readability on mobile EPD devices.
- Long‑term reading effects: studies on visual function and subjective symptoms from extended reading sessions.
- Special populations: evaluation methods for visual impairments (for example, cataract cloudiness) and their impact on tablet/EPD readability.
- Context of use: practical considerations for defining where and how EPDs are used (lighting, task types, user capabilities).
- Annex A: overview of electronic display standardization.
Note: ISO/TR 9241‑312 is an informative technical report (no normative references), intended to present research and recommended evaluation practices rather than mandatory requirements.
Applications
This report is directly applicable to:
- E‑reader and EPD hardware manufacturers
- UX and display engineers designing typographic and UI elements for e‑paper
- Ergonomists and human‑factors professionals conducting readability testing
- Accessibility specialists and clinicians evaluating visual performance for impaired users
- Researchers studying display legibility, contrast, and illumination effects
Who should use it
Product designers, usability researchers, standards experts, display engineers, and regulatory bodies will use this report to design studies, set test conditions, and interpret readability data for electrophoretic (e‑paper) products.
Related standards
- ISO 9241 series (visual ergonomics and human‑system interaction)
For the full technical details and experimental protocols, obtain ISO/TR 9241‑312:2020 from your national standards body or ISO.