Overview
EN ISO 13696:2022 - Optics and photonics: Test method for total scattering by optical components specifies standardized procedures to measure the total scattering produced by coated and uncoated optical surfaces. The method quantifies the combined contributions of forward scattering and backward scattering using an integrating collector (Ulbricht sphere) and describes an alternative Coblentz-hemisphere arrangement. The standard supersedes EN ISO 13696:2002 and updates measurement ranges, symbols, and calibration approaches.
Key topics and technical requirements
- Scope and applicability
- Applies to optical components (coated and uncoated) whose surfaces have a radius of curvature > 10 m.
- Measurement wavelengths: ultraviolet above 250 nm up to the infrared below 15 µm; special procedures are described for the deep ultraviolet (190–250 nm). Scattering is generally negligible above 15 µm.
- Measurement principle
- Collection of scattered light with an integrating (Ulbricht) sphere; optional Coblentz hemisphere described in Annex A.
- Determination of total scattering from measured forward or backward scattering components.
- Test arrangement and equipment
- Radiation source and beam preparation system requirements.
- Integrating sphere design, detector and detection system (including optional lock-in amplifier or fast data acquisition), and specimen holder specifications.
- Calibration and power-measurement procedures (including alternative calibration with a calcium fluoride diffuser disk - Annex E).
- Procedure and evaluation
- Alignment steps for beam and specimen, measurement sequence, and corrections.
- Calculation of total scattering values, error-budget estimation and statistical evaluation examples (Annex C).
- Required content for test reports (Annex B provides an example).
- Symbols and definitions
- Introduces standardized symbols for total scattering (σ_TS), forward scattering (τ_TS) and backward scattering (ρ_TS), plus terms and units.
Applications and users
EN ISO 13696:2022 is intended for:
- Optical component manufacturers and thin-film coating suppliers performing production quality control.
- Metrology and test laboratories validating optical surface quality and scatter losses.
- Laser-system integrators and photonics R&D teams assessing stray light, system efficiency and imaging performance.
- OEMs in optoelectronics, imaging, aerospace and defense where scattering affects system performance.
Practical benefits include consistent, comparable total-scatter data for specification compliance, improved optical design trade-offs, and traceable measurement and calibration methods.
Related standards
- ISO/TC 172 optics and photonics series (see normative references in EN ISO 13696:2022)
- Standards for beam and laser characterization referenced in the document (e.g., ISO 11146 series and ISO 80000-7 cited in the standard’s bibliography)
Keywords: EN ISO 13696:2022, total scattering, optical components, integrating sphere, Ulbricht sphere, forward scattering, backward scattering, optics and photonics, Coblentz hemisphere, deep ultraviolet testing.
