High frequency ultrasound imaging using an active optical detector

摘要

Optical detection of ultrasound has numerous advantages overntraditional piezoelectric methods. These systems offer noncontactninspection, rapid scanning capabilities, fine spatial sampling, andnlarge bandwidths. In addition, difficulties associated with conventionalnultrasound imaging systems such as cross-talk between elements,nelectrical connections, and electromechanical resonances are greatlynreduced or even eliminated. Because of this, high frequency phasednarrays for ultrasound detection can be emulated by accuratelynpositioning and focusing optical beams on a suitable surface, whichndefines array elements. However, optical systems have lower sensitivitynthan their piezoelectric counterparts, limiting their widespread use innultrasound imaging. Active optical detection offers a solution. Annactive ultrasound detector consisting of a neodymium-doped glassnwaveguide laser with an optical demodulation system, was builtndemonstrating enhanced sensitivity while preserving the benefits ofntraditional passive optical detection