ISO 8980-4:2006

Overview

ISO 8980-4:2006 - Ophthalmic optics - Uncut finished spectacle lenses - Part 4: Specifications and test methods for anti-reflective coatings defines optical and non‑optical requirements and standardized test methods for anti-reflective (AR) coatings on spectacle lenses. It sets measurable criteria for reflectance and durability and specifies how to measure spectral, luminous and mean reflectance for uncut finished lenses. The standard explicitly excludes transmittance/absorptance and the colour of reflected light.

Key topics and technical requirements

• Reflectance measurement

  • Spectral range: 380–780 nm; wavelength step ≤ 5 nm; spectral bandwidth (FWHM) ≤ 5 nm.
  • Instrument: dual‑ or single‑beam spectrophotometer with incident angle ≤ 17° and measurement uncertainty < 0.1% for spectral reflectance.
  • Calibration using an uncoated specimen of known refractive index (∆n < 0.001) with matched curvature.
  • Luminous reflectance (ρV) and mean reflectance (ρM) are calculated per ISO 13666.
  • Requirement: measured luminous reflectance shall be < 2.5% (when determined as specified). If a manufacturer quotes reflectance values, measured values must not exceed the quoted values by more than 20%.

• Physical/coating area

  • Usable diameter of coated area for uncut lenses: W(d − 4) mm, where d is the nominal lens diameter indicated by the manufacturer.

• Durability and adhesion testing

  • Type test: combined environmental cycling and rubbing sequences.
  • Environmental sequence: 16 h cycle (temperature, light irradiation and humidity exposure) as described in normative Annex B (e.g., fluorescent/xenon + condensation or xenon + immersion).
  • Rubbing tool and procedure specified in Annex C; inspection conditions in Annex D.
  • Acceptance: Five consecutively tested lenses must show no significant loss of adhesion - defined as more than 3 mm of delamination within the inspected 20 mm central zone leads to failure.

• Documentation

  • Manufacturers must make spectral reflectance curves and luminous/mean reflectance values available on request.

Applications and who uses it

• Spectacle lens manufacturers use ISO 8980-4 for product development, coating specification and quality control of AR coatings.
• Coating suppliers rely on the standard to validate optical performance and durability claims.
• Test laboratories and QA departments implement the described measurement and durability protocols for type testing and conformity assessment.
• Opticians, retailers and regulators reference the standard when evaluating product claims or ensuring compliance for marketed spectacle lenses.

Related standards

• ISO 8980-1, -2, -3 (other parts of uncut finished spectacle lens specifications)
• ISO 13666 (vocabulary and equations for luminous/mean reflectance)
• ISO 14889 (fundamental requirements for uncut finished lenses)
• ISO 9022-9 (xenon irradiation reference for environmental testing)

Keywords: ISO 8980-4:2006, anti-reflective coatings, spectacle lenses, ophthalmic optics, reflectance measurement, luminous reflectance, mean reflectance, durability testing, environmental sequence.