Development of optical transmitters for high-amplitude focused ultrasound

This paper investigates the use of thin-film optical transmitters to generate focused ultrasound, aiming to develop highamplitude focused ultrasound. Composite films were used as the optoacoustic sources, which consist of carbonnanotubes (CNTs) and elastomeric polymers. As the nano-composites work as excellent optical absorbers and efficient heat converters, thermo-elastic volume deformation within the composites produces strong optoacoustic pressure. These films were formed on concave substrates for optoacoustic generation of the focused ultrasound. A focal waveform was measured using a single-mode fiber-optic hydrophone. A peak positive pressure of ~4 MPa was achieved.

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