A fibre optic two-dimensional array sensor for sound field
visualization is presented. The proposed system consists of an optical fibre
network and sensor element installed at every node of the network. The sound
field is measured as an intensity modulation of the optical coupling between
pairs of fibres in the network. In this paper, demonstration of the temporal
and spatial sampling of the distributed sound field by matrix-style access to
the sensor elements with the switching of the light sources is described. A
64-element array was used for stationary field measurement with `slow-mode'
switching, while a 16-element array was made for transient field measurement
with `fast-mode' switching. The present system eliminates the need for
electrical multiplexers to switch the signals, and reduces the number of
cables required to connect the array with the post-processing
unit.