2D imaging of ultrasound fields using CCD array to map output of Fabry-Perot polymer film sensor

A 2D ultrasound field imaging system that uses a CCD array to map the optical output of a planar Fabry-Perot polymer film sensing interferometer is described. This system enables ultrasound fields to be rapidly mapped over a 6.6×4.7 mm aperture with spatial and temporal resolutions of the order of 10 μm and 10 ns, respectively. The concept was successfully demonstrated by imaging the acoustic field at the focus of a pulsed 5 MHz PZT ultrasound transducer. The technique offers an alternative to piezoelectric-based methods for high-resolution biomedical and industrial ultrasonic imaging and field characterisation applications.