The Fabry-Perot interferometer (FPI) is widely used in photoacoustic imaging (PAI) as an ultrasound (US) sensor due to its high sensitivity to weak US waves. Such high sensitivity is important as it allows for increasing the depth in tissue at which PAI can access, thus strongly influencing its clinical applicability. FPI sensitivity is impacted by many factors including the FPI mirror reflectivity, focussed beam spot size, FPI cavity thickness and aberrations introduced by the optical readout system. Improving FPI sensitivity requires a mathematical model of its optical response which takes all of these factors into account. Previous attempts to construct such a model have been critically limited by unrealistic assumptions. In this work we have developed a general model of FPI optical readout which based upon electromagnetic theory. By making very few assumptions, the model is able to replicate experimental results and allows insight to be gained into the operating principles of the sensor.

Date Published: 19 July 2019
PDF: 3 pages
Proc. SPIE 11077, Opto-Acoustic Methods and Applications in Biophotonics IV, 110770H (19 July 2019); doi: 10.1117/12.2527114

Published in SPIE Proceedings Vol. 11077:
Opto-Acoustic Methods and Applications in Biophotonics IV
Vasilis Ntziachristos; Roger Zemp, Editor(s)