Polymer Matrix Nanocomposites as Photoacoustic Transmitters for Epiretinal Prosthetics

Polymer matrix nanocomposites can serve as photoacoustic transmitters in epiretinal prosthetic devices. Pulsed laser excitation of these materials initiates photothermoelastic processes producing acoustic waves that are emitted by the material and can acoustically neuromodulate retinal tissues. For the nanocomposites described in this work, the nanoparticles serve as optical absorbers that rapidly heat the matrix when excited by short duration laser pulses. The localized thermal expansion of the matrix launches ultrasonic waves that propagate in the nanocomposite and can couple to external media by transmission across the material boundary. In this work, these materials are analyzed for use as an acoustic transmitter in an epiretinal prosthetic that might be used to provide functionality to retinal structures that have deteriorated as a result of disease processes.