Fig. 5.

Signals from a red blood cell measured using the 1200 MHz transducer. (A) The measured photoacoustic signal from the center of a single RBC, and (B) the normalized photoacoustic power spectrum from four different RBCs. A similar shape is observed from each power spectrum, with spectral minima occurring around 800 and 1500 MHz. The area outside of the transducer −12 dB bandwidth has been grayed to emphasize the detectable signal.