Photoacoustic generation of focused quasi-unipolar pressure pulses.
نویسندگان
چکیده
The photoacoustic effect was employed to generate short-duration quasi-unipolar acoustic pressure pulses in both planar and spherically focused geometries. In the focal region, the temporal profile of a pressure pulse can be approximated by the first derivative of the temporal profile near the front transducer surface, with a time averaged value equal to zero. This approximation agreed with experimental results acquired from photoacoustic transducers with both rigid and free boundaries. For a free boundary, the acoustic pressure in the focal region is equal to the sum of a positive pressure that follows the spatial profile of the optical energy deposition in the medium and a negative pressure that follows the temporal profile of the laser pulse.
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ورودعنوان ژورنال:
- Journal of innovative optical health sciences
دوره 3 4 شماره
صفحات -
تاریخ انتشار 2010