Acousto-optic sensing - spatial reconstruction of the sound field enclosed in a room

摘要

Measuring the sound pressure field over medium and large volumes, such as rooms, can be cumbersome. Conventional sensing methods acquire the sound pressure (or other field quantity) at a single point. Therefore, to acquire the three-dimensional sound filed in a room, a large number of measurement points must be distributed throughout. In this study, we propose a method to capture the sound field in a volume based on the acousto-optic effect. The acoustic pressure field is captured along beams of laser light. As the light (the sensing element of this method) travels through the sound field, it captures information of the sound pressure along its travel path. In this study, the spatial reconstruction of the sound field in a room from acousto-optic measurements is presented and compared with conventional point-wise measurements. The results show a first approach to the spatial characterisation of the sound field in a room using the acousto-optic sensing principle.