Hydrophones based on interferometric fiber-optic sensors with applications in photoacoustics

Biomedical imaging used for medical diagnosis constantly requires improvement in the characteristics for imaging devices. The sensing devices are one of the most important pieces to improve in order to get images with better quality. In this thesis, it is proposed the use of interferometric fiber-optic sensors (which offer the advantages inherent to optical fibers) as devices to detect pressure/acoustic signals generated by the photoacoustic effect. It is explored the capability of using fiber-optic interferometric hydrophones in order to determine the thickness of a material derived from the acoustic signal generated when a sample is illuminated. In addition, the analysis of photoacoustic signals generated by the excitation of nanoparticles of an anisotropic material as absorption centers. Finally, the cross-section of a metallic sample was photoacoustically imaged by acquiring the pressure signals generated.