Overview
ISO 17915:2018 - "Optics and photonics - Measurement method of semiconductor lasers for sensing" defines standardized measurement methods for characterizing semiconductor lasers used in optical sensing. The standard covers methods to measure the temperature and injected current dependence of lasing wavelength, and the lasing spectral line width. It applies to a wide range of semiconductor lasers (edge-emitting, VCSEL, bulk, quantum-well, strained quantum-well, interband cascade and quantum cascade lasers) used in industrial, medical, agricultural and environmental sensing.
Key topics and technical requirements
- Measurement scope
- Characterization of wavelength shifts with ambient temperature and drive current.
- Determination of spectral line width (linewidth) relevant to sensor resolution and stability.
- Laser types covered
- Edge-emitting (DFB, DBR, FP, external cavity), vertical-cavity surface-emitting lasers (VCSEL), quantum well, quantum cascade and interband cascade lasers.
- Measurement methods and procedures
- Defined setups and requirements for temperature-dependence and current-dependence tests, including static and dynamic current coefficients.
- Techniques for linewidth measurement such as two-laser beat methods and self-delayed heterodyne arrangements (described in Clause 7).
- Precautions, required instrumentation and step-by-step measurement procedures to ensure repeatability and traceability.
- Informative annex
- Annex A lists essential ratings and characteristics for semiconductor lasers used in sensing-helpful for test planning and specification.
- Normative linkage
- Measurements are to be performed in accordance with ISO 13695 (test methods for spectral characteristics of lasers).
Practical applications and who should use it
- Sensor manufacturers - to qualify laser modules for gas sensing, bio-sensing, photoacoustic and absorption spectroscopy systems.
- Laser component and diode manufacturers - for product specification, quality control and datasheet values (wavelength vs. temperature/current, linewidth).
- R&D and test laboratories - to perform comparable, traceable measurements when developing tunable laser absorption spectroscopy (TLAS), cavity ring-down spectroscopy (CRDS), photoacoustic spectroscopy (PAS) and related techniques.
- System integrators and OEMs - to select lasers with appropriate wavelength stability and linewidth for environmental monitoring, medical diagnostics and agricultural sensing.
- Regulatory and conformity assessors - to verify measurement methods and reported characteristics.
Related standards
- ISO 13695 - Lasers and laser-related equipment - Test methods for the spectral characteristics of lasers (normative reference cited by ISO 17915:2018).
Keywords: ISO 17915:2018, semiconductor lasers measurement, laser wavelength measurement, spectral linewidth, tunable laser absorption spectroscopy, cavity ring down spectroscopy, photoacoustic spectroscopy, laser sensing.
