Finite element simulation of laser based optical generation of ultrasound

There is growing interest in microscopic 2D arrays for very high resolution imaging. One approach, based on using a scanned laser for both generation and detection of acoustic waves, has been proposed by the University of Michigan ultrasound group. Various design improvements have been advanced. These include: changing the thermoelastic source material (replacing Chromium with Polydimethylsiloxane (PDMS)) and eliminating the glass substrate (by replacing it with an all PDMS structure). In this paper we investigate the impact of these design changes and also consider the impact of laser spot size using PZFlex Finite Element Analysis (FEA). In particular, a thermoelastic coupling capability was introduced, and tested, in the FEA simulations.