Overview
IEC TS 61966-13:2023 - Multimedia systems and equipment - Colour measurement and management - Part 13 - specifies an objective measurement method for observer metamerism (OM) in displays. The Technical Specification defines a colour-difference metric and a repeatable measurement procedure to quantify how display colour appearance varies between observers due to differences in spectral power distributions (SPDs). The published 2023 edition (with Corrigendum 1 included) targets light‑emitting and backlit transmitting colour displays measured under dark‑room conditions.
Key topics and technical requirements
- Observer metamerism metric: A defined objective colour‑difference metric to quantify observer‑dependent colour mismatches between stimuli with different SPDs.
- Measurement method: Procedures for obtaining the metric, including steps for colour matching, SPD measurement and colour difference computation.
- Measuring equipment: Specification of required light‑measuring devices (e.g., spectroradiometers) and the viewing/measurement direction coordinate system used to record directional measurements.
- Measuring conditions: Standard environmental and set‑up conditions such as power supply, warm‑up time, dark‑room requirements, and DUT placement to ensure repeatability.
- Colour‑matching functions (CMFs): Use of individual CMFs and procedures to generate or select CMFs for observer populations (age and field‑size considerations are addressed).
- Reference colours and reporting: Defined reference XYZ values, reference colour sets, the Observer Metamerism Index (OMI) computation, and a standard reporting form and graphs for results.
- Informative annexes: Practical material including generating individual CMFs, XYZ reference data, measurement method for comparing different displays, multi‑ORU (optical radiant unit) colour‑matching processes, and worked examples.
Applications and who should use it
- Display manufacturers: For characterizing and reducing observer metamerism in product design and quality control.
- Colour scientists and metrology labs: To perform standardized OM measurements and publish consistent, comparable results.
- Calibration and QC service providers: For objective assessment of colour uniformity and observer dependence across multiple displays or device types.
- System integrators and content creators: To understand cross‑display colour consistency issues that affect multi‑display workflows.
Keywords: IEC TS 61966-13:2023, observer metamerism, colour measurement, spectral power distribution, display calibration, colour‑matching functions, spectroradiometer, dark‑room conditions.
Related standards
- IEC 61966 series (general colour measurement and management guidance)
- CIE publications on observer models (for example CIE Pub. 170-1:2006), which the TS references for observer CMF models and age adjustments.