This simulation illustrates how a photoacoustic signal is produced. Furthermore it shows us how a real, measureable signal shall look like if the conditions of thermal and stress confinement are fullfilled.
The starting point is, the solution of the photoacoustic equation for a absorbing spherical object with a given radius , that is homogeneously heated by a delta pulse. For details go to e.g. Master thesis
Grueneisen relaxation photoacoustic microscopy with optical ultrasonic detection.
The propagating parts of this formula can be displayed as the following
...Distance source <-> detector [m]
...Speed of sound in water [m/s]
...Initial pressure rise [Pa]
which results in a N-shaped pulse
Excited with a gaussian shaped laserpulse and detected with a ultrasonic detector with finite bandwidth and a defined center frequency the measureable pulse looks like this
python runSim.pystarts the simulation and states the simulation process.
-
Simulation of
- different sensor bandwidths and center frequencies
- multible target sizes
- pulselengths of the laser
-
Implementation of a more complex heating funciton
This project is licensed under the GNU GPLv3 License - see the LICENSE file for details