High-resolution photoacoustic thermal-wave microscopy

Abstract

Experiments on photoacoustic thermal‐wave microscopy are presented, for the first time, at high resolution. Using piezoelectric detection and a modulation frequency of 185 kHz, we obtain a thermal‐wave resolution of ∼7 μm. We show that the photoacoustic phase signal provides true thermal‐wave imaging even in the presence of surface features with strong optical contrast.