ISO CIE 11664-2-2022 PDF

Full title and description

ISO/CIE 11664-2:2022 — Colorimetry — Part 2: CIE standard illuminants. This international standard defines three CIE standard illuminants (A, D65 and D50) and provides their relative spectral power distributions for use in colorimetric calculations and color assessment.

Abstract

This document specifies CIE standard illuminant A (typical tungsten‑filament/incandescent lighting), CIE standard illuminant D65 (average daylight, ≈6500 K) and CIE standard illuminant D50 (daylight, ≈5000 K). Relative spectral power distributions for these illuminants are given (values at 1 nm intervals from 300 nm to 830 nm) and the standard includes definitions, formulae and tabulated data needed for reproducible colorimetric work.

General information

• Status: Published
• Publication date: August 2022
• Publisher: ISO in cooperation with the CIE (ISO/CIE joint publication)
• ICS / categories: 17.180.20 (Colours and measurement of light)
• Edition / version: Edition 1 (2022)
• Number of pages: 32

Details above are taken from the ISO/CIE publication record for ISO/CIE 11664‑2:2022.

Scope

The standard defines the spectral power distributions and associated definitions for three normative CIE illuminants: A (incandescent/tungsten-like), D65 (average daylight, nominal CCT ≈ 6500 K) and D50 (daylight, nominal CCT ≈ 5000 K). It provides the formula for illuminant A, tabulated SPD data (300–830 nm at 1 nm intervals) for practical use, and guidance on the concepts of an illuminant (defined SPD) versus a physical source or realization.

Key topics and requirements

• Definitions of the three CIE standard illuminants (A, D65, D50) and their intended representative lighting conditions.
• Normative spectral power distribution (SPD) data provided at 1 nm intervals from 300 nm to 830 nm for each illuminant.
• Mathematical definition (formula) for illuminant A and practical SPD tables for all three illuminants.
• Clarification of terminology (illuminant vs physical source) and notes on source realizations; practical lamp description for source A and lack of recommended physical sources for D65/D50 within this document.
• Use of the SPDs and definitions as normative inputs for colorimetric calculations and harmonization of measurement practice.

Typical use and users

Used by color scientists, calibration and test laboratories, display and lighting manufacturers, printing and packaging professionals, textile and paint industries, standards developers, and anyone performing colorimetric calculations or color matching where standardized illuminants are required. Typical applications include colorimetry, color quality assessment, specification of viewing conditions, device characterization and product conformance testing.

Related standards

This part is one element of the ISO/CIE 11664 series (colorimetry). Closely related parts include ISO/CIE 11664‑1 (CIE standard colorimetric observers — under development/related work), ISO/CIE 11664‑3 (CIE tristimulus values), ISO/CIE 11664‑4 (CIE 1976 L*a*b*), ISO/CIE 11664‑5 (u',v' and L*u*v* related material) and ISO/CIE 11664‑6 (CIEDE2000 colour‑difference formula). ISO/CIE 11664‑2:2022 revises and replaces the earlier ISO 11664‑2:2007 edition.

Keywords

Colorimetry; CIE standard illuminants; Illuminant A; D65; D50; spectral power distribution (SPD); correlated colour temperature (CCT); color measurement; color matching; standard illuminant tables.

FAQ

Q: What is this standard?

A: ISO/CIE 11664‑2:2022 specifies the CIE standard illuminants A, D65 and D50 and provides their normative spectral power distributions for use in colorimetric calculations and standardized color assessment.

Q: What does it cover?

A: It covers definitions, formulae and tabulated SPDs (300–830 nm at 1 nm intervals) for illuminants A, D65 and D50, plus explanatory notes on terminology and practical considerations for source realization.

Q: Who typically uses it?

A: Color scientists, testing and calibration laboratories, lighting and display manufacturers, printers, textile and paint industries, metrology institutes, and standards bodies that need reproducible, standardized illuminants for measurement and specification.

Q: Is it current or superseded?

A: ISO/CIE 11664‑2:2022 is the current published edition (published August 2022) and it supersedes the earlier ISO 11664‑2:2007 edition.

Q: Is it part of a series?

A: Yes — it is Part 2 of the ISO/CIE 11664 series on colorimetry. Other parts cover observers, tristimulus values, colour spaces (L*a*b*, L*u*v*), uniform chromaticity diagrams and colour‑difference formulas.

Q: What are the key keywords?

A: Illuminants A, D65, D50; spectral power distribution; colorimetry; correlated colour temperature; SPD tables; color measurement.