Overview
IEC 62679-3-1:2014, issued by the International Electrotechnical Commission (IEC), establishes standardized measuring conditions and optical measuring methods to evaluate the optical performance of Electronic Paper Displays (EPDs). This standard applies to EPDs using segment, passive, or active matrix technologies, whether monochrome or color, and is intended specifically for devices operating in reflective mode. Although some EPDs feature integrated lighting units (ILUs), the standard requires that these be turned off during measurement. The methodology is not applicable to color systems using more than three primary colors. By harmonizing measurement practices, IEC 62679-3-1:2014 helps manufacturers, testers, and users ensure accurate, reproducible, and comparable results for optical characteristics in EPD technology.
Key Topics
- Measurement Scope: Focus on optical performance metrics for EPDs under reflective mode; covers both monochromatic and color (up to three primaries) displays.
- Standard Environments: Specifies environmental conditions such as a temperature of 25°C ±3°C, relative humidity between 25% and 85%, and controlled illumination.
- Measurement Geometry:
- Defines coordinate systems for viewing direction, including angle of inclination and rotation.
- Prescribes standardized lighting conditions, including ambient and directional illumination to simulate real-world indoor and outdoor environments.
- Illumination Types:
- Hemispherical diffuse illumination: Simulates ambient, room, or skylight conditions.
- Directional illumination: Simulates sunlight or focused artificial lighting.
- Prescribed illuminants include CIE Standard Illuminant A, D65, D50, and D75.
- Optical Characteristics Measured:
- Reflection and Reflectance Factors
- Photometric In-plane Uniformity
- Contrast Ratio and Ambient Contrast Ratio
- Cross-talk and Ghosting
- Display Colour and Colour Gamut
- Daylight Display Colour and Gamut Volume
- Viewing Direction Dependence (how display properties change at various angles)
- Measurement Equipment: Includes requirements for light measuring devices and alignment procedures.
Applications
- Display Manufacturing and R&D: Ensures consistent quality control and specification development for EPD production, particularly for e-readers, digital signage, smart labels, and low-power displays.
- Product Testing & Certification: Laboratories and certification bodies use the standard to evaluate and compare display performance across different products and manufacturers.
- Procurement and Specification: Enables clear communication of EPD performance in supply chain contracts and technical documentation.
- End-User Guidance: Provides benchmarks for product designers and engineers to select suitable EPD solutions based on standardized optical performance data, relevant for applications in consumer electronics, industrial devices, and public information systems.
Related Standards
- IEC 62679-1-1 – Electronic paper displays – Part 1-1: Terminology (for definitions and foundational concepts)
- IEC 61966-2-1 – Multimedia systems and equipment – Colour management – Default RGB colour space – sRGB (color measurement reference)
- IEC 60050 – International Electrotechnical Vocabulary (authoritative terms and definitions)
- CIE 15 – Colorimetry (illuminant specifications and colorimetric standards)
- SID Display Measurement Standard (referenced for best practices in display metrology)
By following IEC 62679-3-1:2014, organizations can achieve comparable, precise, and industry-recognized measurements of EPD optical performance-an essential requirement for global competitiveness and compliance in the rapidly evolving electronic display sector.