Term: free-running laser
https://doi.org/10.1351/goldbook.F02521

Definition:
A term applied to a pulsed laser, meaning that the laser emission lasts as long as the pumping process is sufficient to sustain lasing conditions. Typical pulse durations are in the µs-ms range, depending on the pumping source. When the operation mode of a pulsed laser is not specified as mode-locked, Q-switched, or anything else, it must be considered as free-running.

Related Terms:
1) laser (http://doi.org/10.1351/goldbook.L03459).
2) lasing (http://doi.org/10.1351/goldbook.L03479).
3) mode (http://doi.org/10.1351/goldbook.M03958).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2244 (https://doi.org/10.1351/pac199668122223)

Citation: 'free-running laser' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.F02521

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