摘要
Photoacoustic and photothermal spectroscopy methods can be effectively applied to the characterization of single microparticles. As the optical beam deflection method, in which a thermal wave generated by non‐radiative transition is detected by deflection of a probe beam, is sensitive for a single microparticle, and is a remote‐measurement method without using a cell, it is suitable for nondestructive characterization of microparticles. This method was applied to determination of chemical species adsorbed on a single microparticle, and spectral differences between leukemia and normal white blood corpuscles could be obtained. A more violent photothermal conversion phenomenon of a particle, laser breakdown and accompanying plasma and acoustic emission, was applied to individual detection and analysis of ultrafine particles in liquids. Laser‐like nonlinear emission from the plasma was observed. Copyright © 1993 Society of Chemical Industry