Acoustic Steering Using Thermally Induced Optical Reflection of Sound (THORS)

Author/Creator ORCID

Date

2021-03-12

Department

Program

Citation of Original Publication

Kazal, Daniel S., An Ngo, Ellen L Holthoff, and Brian Cullum. “EXPRESS: Acoustic Steering Using Thermally Induced Optical Reflection of Sound (THORS).” Applied Spectroscopy, (March 2021). https://doi.org/10.1177/00037028211004601.

Rights

Public Domain Mark 1.0
This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law

Subjects

Abstract

Using the recently discovered THORS phenomenon, it is possible to generate optically induced, local density barriers in air by the absorption of intense, modulated laser light (the THORS phenomenon), which results in abrupt differences in compressibility of the air at these barriers that can efficiently reflect incident acoustic waves. In this note, we demonstrate the ability to optically manipulate and reflect acoustic waves in air as well as optimize the functional parameters (optical modulation and acoustic frequency) and characterize the effects of common physical parameters, including localized thermal gradients and incident angle of reflection on the efficiency of the resulting acoustic reflection. Finally, the ability to efficiently steer acoustic waves around a physical obstruction using THORS is also demonstrated.