Overview
ISO 20473:2007, "Optics and photonics - Spectral bands," specifies a standardized division of optical radiation into spectral bands for use in optics and photonics. The standard defines wavelength-based band limits (with corresponding approximate frequency, wavenumber and photon energy values) and clarifies terminology - notably restricting the term “light” to visible radiation (380 nm to 780 nm). ISO 20473 excludes lighting, telecommunication applications and occupational hazard protection.
Key topics
- Spectral band definitions: Wavelength-based band limits are given in Table 1. Examples (as specified) include:
- Extreme UV (EUV): 1–100 nm
- Vacuum UV (VUV): 100–190 nm
- Deep UV (DUV): 190–280 nm
- UV-B: 280–315 nm
- Near UV / UV-A: 315–380 nm
- Visible (VIS, “light”): 380–780 nm
- Near IR / IR‑A: 780–1 400 nm
- IR‑B: 1 400–3 000 nm
- Mid IR (MIR): 3 000–50 000 nm
- Far IR (FIR): begins at 50 000 nm
- Inclusive band limits: Band edges are included in both adjacent bands (i.e., overlaps at boundaries).
- Vacuum vs. medium: Relations among wavelength, frequency, wavenumber and photon energy are strictly valid for vacuum; when relevant, the medium’s refractive index must be considered.
- Terminology note & rationale: Annex A explains the choice of the 380 nm boundary between UV‑A and visible for optics and photonics (aligned with ophthalmic practice and material considerations).
Applications
ISO 20473:2007 is practical for professionals who need a common, unambiguous spectral vocabulary and band delimitation in optics and photonics contexts:
- Optical system and sensor design (spectrometers, detectors, imaging systems)
- Optical component specification and testing (filters, lenses, coatings)
- Photonics R&D, laboratory reporting and data comparability
- Product datasheets, calibration protocols and technical documentation
- Education, standards alignment and interoperability among manufacturers and test labs
It is not the reference for lighting engineering, telecom wavelength allocation, or occupational optical‑radiation safety - those domains use different band definitions.
Who uses this standard
- Optical and photonics engineers
- Manufacturers of optical components and instruments
- Calibration and test laboratories
- Standards committees and technical writers preparing product specifications
Related standards
- ISO 13666 (ophthalmic optics vocabulary) - referenced for eye‑related effects
- IEC 60050‑845 / CIE Publication No. 17.4 - lighting and lighting vocabulary, alternative definitions (e.g., UV‑A boundary sometimes given as 400 nm)
Keywords: ISO 20473, spectral bands, optics and photonics, wavelength ranges, UV visible infrared, spectral band definitions.
