Overview
EN ISO 13697:2006 (CEN adoption of ISO 13697:2006) specifies high-precision test methods for measuring the specular reflectance and regular transmittance of optical laser components. It defines optical measurement arrangements, calibration procedures and evaluation rules that deliver accuracy far exceeding earlier methods (for example ISO 15368). The standard is aimed at laser- and photonics-related components where very precise optical performance data are required.
Key topics and requirements
- Measurement principles: Optical determination of specular reflectance and regular transmittance as ratios of regularly reflected/transmitted power to incident power under stable temperature and power-density conditions.
- Test arrangements: Use of an optically flat, highly reflective chopper mirror to create alternating probe and reference beams which are directed to the same integrating-sphere target; arrangements for near‑normal incidence and for variable incidence (angular dependence).
- Beam and detector setup: Requirements for laser beam preparation (telescope, pinhole), modulation/chopping, integrating sphere detection and signal extraction at defined modulation frequencies.
- Calibration procedures: Two-step calibration to determine the reflectance of the chopper mirror and any additional deflecting mirror, enabling computation of the sample’s specular reflectance or transmittance from measured probe/reference power signals.
- Test procedure details: Steps for sample preparation, chopper mirror calibration, measurement of near-normal specular reflectance, angular dependence of reflectance, and regular transmittance measurements.
- Evaluation and reporting: Methods to compute reflectance/transmittance from measured power differences and to document test conditions, uncertainties and results in a standardized test report.
- Precision focus: Test methods optimized to achieve measurement accuracy multiple orders of magnitude better than some prior standards.
Applications and users
- Who uses it: optical metrology laboratories, laser optics manufacturers, coating suppliers, quality assurance teams, R&D groups in optics and photonics, and system integrators requiring traceable, high-accuracy optical data.
- Practical uses:
- Verifying high-reflectance mirrors, beam-steering optics and coated substrates.
- Characterizing anti-reflection coatings, windows and transmissive components for laser systems.
- Quality control and acceptance testing of optical components used in precision laser instruments, sensing and research applications.
- Producing traceable measurement data for optical component specifications and supplier declarations.
Related standards
- ISO 15368 - earlier measurement procedures (less precise compared with ISO 13697)
- ISO 11145 - vocabulary and symbols for lasers and optical instruments
- ISO 31-6 - quantities and units for light and electromagnetic radiations
- ISO 14644-1 - cleanroom classification (relevant for sample preparation/environment control)
Keywords: specular reflectance, regular transmittance, optical laser components, integrating sphere, chopper mirror, calibration, laser optics metrology, EN ISO 13697:2006.