Overview
ISO 24013:2023 - "Optics and photonics - Lasers and laser-related equipment - Measurement of phase retardation of optical components for polarized laser radiation" - specifies standardized test methods for determining the linear optical phase retardation introduced by optical components when illuminated by polarized laser beams. The document is intended for use with transmissive and reflective optics and defines measurement principles, sample preparation, alignment/calibration, test procedures, evaluation and test reporting.
Key topics and technical requirements
- Measurement principle: The phase retardation is obtained from changes in the state of polarization after the optical component is illuminated with a defined polarized laser beam. Use circularly polarized probe beams when expected retardation is near zero, and linearly polarized probe beams when expected retardation is close to π/2.
- Test arrangement: A laser source, polarizer (to generate linear or circular polarization), the test sample, an analyser and a power detector are required. Reflective tests use an alignment laser and positional sensitive detector for reproducible angle alignment.
- Sample preparation and environment: Storage, cleaning and handling per manufacturer instructions; recommended test environment is dust-reduced filtered air (e.g., clean-room ISO class 7) with 40–60% relative humidity.
- Alignment and tolerances:
- Angle of incidence shall match manufacturer’s specifications; deviation for reflective samples shall be controlled (example tolerance in the standard: less than 2 mrad).
- For linearly polarized probe beams on reflective samples, the polarization direction relative to the plane of incidence should be π/4 rad ± 2 mrad.
- Polarization purity and verification: The state of polarization must be prepared and verified with the analyser before inserting the sample. Optical elements in the setup should not significantly degrade the prepared polarization state.
- Procedures and evaluation: The standard provides separate test procedures and evaluation methods for near-zero and near-π/2 retardances, including cases with and without absorptance differences between polarization directions.
- Reporting: Clause 9 defines the content of the test report to ensure traceability and reproducibility.
Practical applications and users
ISO 24013:2023 is used by:
- Optics manufacturers and suppliers for incoming/outgoing quality control of waveplates, polarizers, mirrors, coatings and beam-splitting optics.
- Test and calibration laboratories performing polarization metrology and acceptance testing.
- R&D and system integrators validating polarization-sensitive laser systems (e.g., circular-polarization generation, polarization-maintaining optics).
- Quality assurance teams in photonics and laser manufacturing who require standardized, repeatable phase-retardation measurements.
Practical benefits include consistent acceptance criteria, reproducible alignment/calibration workflows, and traceable reporting for procurement and compliance.
Related standards
- ISO 11145 - Vocabulary and symbols (optics and photonics)
- ISO 12005 - Test methods for laser beam parameters - Polarization
- ISO 14644-1 - Cleanroom classification (referenced for test environment recommendations)
Keywords: ISO 24013:2023, phase retardation measurement, polarized laser radiation, optics and photonics, polarization testing, laser component metrology, phase retarders.