TS ISO 80000-7

TS ISO 80000-7 is a part of the Quantities and Units series that systematically defines the names, symbols, definitions and units for quantities used in light and optical radiation. This part covers quantities used in the wavelength range of approximately 1 nm to 1 mm, and where appropriate it also gives conversion factors. In practice, it brings together the core terminology used for photometric and radiometric work under one consistent framework.

A common technical language for light and optical radiation

The subject of this standard is the correct distinction between quantities related to human visual perception of light and the physical quantities used to describe optical radiation. In general technical context, light is usually expressed through photometric quantities linked to vision, while optical radiation is described with radiometric quantities such as energy, power and spectral distribution. Although both belong to the same electromagnetic region, their definitions and units serve different purposes. A terminology standard like this helps keep engineering, laboratory measurement, lighting and optical systems aligned in a shared vocabulary.

What this kind of standard helps organise

• Names and symbols for quantities in a single coherent system.
• Definitions and SI-aligned units presented together.
• Conversion factors where they are relevant for related quantities.
• Clear separation of photometric and radiometric concepts.

As part of the ISO 80000 series, this document supports consistent calculation, measurement and technical reporting in fields that work with light. That is especially valuable in optical design, lighting engineering, imaging and radiation measurement, where precise quantity naming is essential for comparing results and avoiding ambiguity.