Plane wave acousto-optic imaging in reflection mode geometry

We investigate the possibilities of improving performance of an acousto-optic imaging system operating in reflection mode geometry with linear ultrasound array and optodes in direct contact with a sample by using plane ultrasound waves instead of focused pulses. Differences in acoustic pressure field distributions for various transducer excitation patterns were determined numerically. Acousto-optic images of phantoms with optically absorbing inclusions were obtained experimentally by measuring laser speckle contrast decrease due to the light modulation by plane wave and focused ultrasound pulses. The light fluence rate maps reconstructed using plane wave imaging proved to be clearer and more distinct