Term: thermal lensing
https://doi.org/10.1351/goldbook.T06304

Definition:
A technique that determines the alteration in the refractive index of a medium as a result of the temperature rise in the path of a laser beam absorbed by the medium. The lens produced (usually divergent) causes a change (usually a decrease) in the irradiance measured along the laser beam axis.

Related Terms:
1) photothermal effects (http://doi.org/10.1351/goldbook.P04656).
2) refractive index (http://doi.org/10.1351/goldbook.R05240).
3) laser (http://doi.org/10.1351/goldbook.L03459).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2279 (https://doi.org/10.1351/pac199668122223)

Citation: 'thermal lensing' 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.T06304

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