A number of recently developed techniques for fine particle and aerosol measurement employ focused high‐irradiance (power per unit area) laser beams. A knowledge of the temperature profiles in the media surrounding microsamples and the temperature of the microsample is essential for the design and operation of these instruments. In this paper, we develop theoretical models to estimate the final temperature and temperature profiles associated with microscopic particles heated by intense laser beams. We conclude that a heat‐sinking medium, such as sapphire, can be effective in maintaining sample temperatures at acceptable levels for nondestructive analysis. This paper also examines the time required for particle temperatures to reach a steady‐state time‐independent value. These results are useful for assessing the effectiveness of laser power modulation techniques in these instruments. And finally, the above results are used to calculate the optical path‐length changes near the heated microparticle due to temperature rises in the host medium.
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