摘要
The linear response theory was applied to analyze the phase shift of photoacoustic (PA) signal generated in liquids. Phase shifts of PA signals from turbid solutions were obtained. The linear relationship between the tangent of the phase shift and the beam modulation frequency, predicted theoretically, was experimentally confirmed using polystyrene turbid solution. A novel method for characterization of turbid particles was proposed based on the theory. The experimental value of the heat transfer coefficient ((2.7+0.2) X 10 Jcm K ) of polystyrene turbid particle (radius: 2.5μm) agreed well with the theoretical values. © 1985 IOP Publishing Ltd.