Speaker
Description
Introduction
Photoacoustic tomography (PAT) has the potential as a method for measuring the oxygen saturation of the blood in the human brain. Therefore, ultrasensitive detectors are needed to measure ultrasound signals through the human skull. The aim of this work is to investigate and optimise the sensitivity of plano-concave optical sensors. It should be clarified whether the Gaussian beam width has an influence on the phase sensitivity of optical sensors.
Method
A method for calibrating the beam width for a measurement setup was developed. The effects of beam widths on the optical phase sensitivity are simulated by an ABCD-transfer-matrix-method. We modified the experimental setup to measure the sensitivity with the matching beam width from the simulation.
Result
The beam width has an effect on the sensitivity of planoconcave optical sensors. Depending on the radius of curvature and the reflectivity of the mirrors of the optical detectors, the highest phase sensitivity exists at a certain beam width. The phase sensitivity could thus be increased by fifty percent.
