2D photoacoustic scanning imaging with a single pulsed laser diode excitation

A portable near-infrared photoacoustic scanning imaging system has been developed with a single pulsed laser diode, which was integrated with an optical lens system to straightforward boost the laser energy density for photoacoustic generation. The 905 nm laser diode provides a maximum energy output of 14 μJ within 100 ns pulse duration, and the pulse repetition frequency rate is 0.8 KHz. As a possible alternative light source, the preliminary 2D photoacoustic results primely correspond with the test phantoms of umbonate extravasated gore and knotted blood vessel network. The photoacoustic SNR can reach 20.6±1.2 dB while signal averaging reduces to 128 pulses from thousands to tens of thousands times, and the signal acquisition time accelerates to less than 0.2 s in each A-scan, especially the volume of the total radiation source is only 10 × 3 × 3 cm 3 . It demonstrated that the pulsed semiconductor laser could be a candidate of photoacoustic equipment for daily clinical application.