In this paper, we describe a narrow-bandwidth generation and detection of photoacoustic (PA) signals in biological specimens using frequency-domain photoacoustics. An intensity-modulated laser was used for PA generation, and a homodyne Michelson interferometer coupled to a lock-in amplifier was used for optical PA detection. The amplitude and phase of the PA signal were measured at the modulation frequency as the frequency was swept over the bandwidth of interest. A synthesized pulse response was obtained using time-domain reconstruction and the absorber map was estimated using k-space reconstruction methods. Experimental results obtained from 500-μm graphite rods embedded in tissue-mimicking phantoms and slide-mounted tissue samples are presented along with their respective time-domain and time-reversal reconstruction maps.

Date Published: 21 May 2015
PDF: 6 pages
Proc. SPIE 9487, Smart Biomedical and Physiological Sensor Technology XII, 94870H (21 May 2015); doi: 10.1117/12.2177426

Published in SPIE Proceedings Vol. 9487:
Smart Biomedical and Physiological Sensor Technology XII
Brian M. Cullum; Eric S. McLamore, Editor(s)