Fig. 5.

PLCI experimental setup. Pulsed outputs of the excitation laser (660 nm) and photoacoustic laser (840 nm) were combined with a bifurcated light guide and illuminate the target. The time delay between the excitation and probe pulses was controlled by an electronic synchronization circuit. The solutions were placed in two plastic tubes and scanned horizontally. The generated acoustic waves were detected by a focused ultrasound transducer. Sync out: synchronization output.