IEC 62977-2-11:2023

Overview

IEC 62977-2-11:2023 - Electronic displays: Measurement of optical characteristics - Local luminance and uniformity - defines standardized methods for measuring local luminance and local luminance uniformity of emissive displays. The standard focuses on measurements performed with a light measuring device (LMD) whose measurement field covers more than 500 pixels of TVs, monitors or signage displays. It targets the detection and quantification of optical variations within a specified local block (an area with at least 500 regularly arranged emission pixels), rather than spatially integrated results across the entire panel.

Key topics and technical requirements

• Scope and definitions: Clear definitions of local block, local luminance, local luminance consistency (LLC), local contrast consistency (LCC) and local luminance uniformity (LLU).
• Standard setup conditions: Requirements for the light measuring device (LMD) and imaging LMD (iLMD), measurement distance, measurement-field angle, environmental conditions (including darkroom and power/warm‑up conditions) and measuring-direction setup.
• Test patterns: Prescribed reference and emissive-patterns, including a 4% white-box reference pattern and emissive ratio–variable patterns; arrangements of regularly scattered emission pixels are used to reveal local non-uniformities.
• Measurement methods: Procedures for assessing
  • local luminance consistency (variation range within the local block),
  • local contrast consistency,
  • local luminance uniformity (variation among adjacent pixels). Results are reported in standardized units and percentages (e.g., LLC, LCC, LLU) to support repeatable comparison.
• Measurement coverage and pixel-count rules: The LMD measurement field must include more than 500 pixels and guidance is given on how many pixels and how the test patterns should cover the measurement field.
• Reporting and examples: The standard includes guided measurement points, example result tables and illustrative figures to ensure consistent implementation.

Practical applications and users

IEC 62977-2-11:2023 is intended for professionals who evaluate emissive display optical performance:

• Display manufacturers (OLED, microLED, etc.) - for R&D, production verification and quality control.
• Test laboratories and certification bodies - for standardized, repeatable measurements and reporting.
• OEMs and procurement teams - to specify and verify local luminance and uniformity in supplier contracts.
• Signage and broadcast integrators - to assess local non‑uniformities that affect image quality in large displays. Applying this standard helps identify pixel-to-pixel cluster deviations, improve manufacturing yield, and produce consistent user-facing image quality.

Related standards

• IEC 62341-1-2 (OLED displays - terminology and symbols)
• IEC 60050-845 (Electrotechnical vocabulary - lighting)
• CIE 70-1987 (Measurement of absolute luminous intensity distributions)

Keywords: IEC 62977-2-11:2023, local luminance, luminance uniformity, emissive displays, LMD, display testing, OLED, microLED, measurement standard.