An integrated optoacoustic transducer combining etalon and black polydimethylsiloxane (PDMS) structures has been designed and developed. The device consists of an 11-μm-thick black PDMS film confined to a 2-mm-diameter circular region acting as an optoacoustic transmitter, surrounded by a 5.9-μm Fabry-Perot polymer etalon structure serving as an optoacoustic detector array. A pulsed laser is focused onto a 30-μm spot on the black PDMS film, defining the transmit element, while a CW laser probes a 20-μm spot on the etalon for ultrasound detection. Pulse-echo signals display center frequencies of above 30 MHz with bandwidths of at least 40 MHz. A theta-array is formed for 3-D ultrasound imaging by mechanically scanning the generation laser along a 1-D array and the detection laser around an annular array. Preliminary images with 3 metal wires as imaging targets are presented. Characterization of the device's acoustical properties, as well as preliminary imaging results, suggest that all-optical ultrasound transducers are potential alternatives to piezoelectric techniques for high-frequency 2-D arrays enabling 3-D high-resolution ultrasound imaging.
|Original language||English (US)|
|Number of pages||7|
|Journal||IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control|
|State||Published - Dec 2008|
Bibliographical noteFunding Information:
manuscript received February 2, 2008; accepted July 2, 2008. This work is supported in part by nIH under grants Eb003455, Eb003449 and Eb004933. y. Hou, s. ashkenazi, and s.-W. Huang are with the departments of Electrical Engineering & computer science and biomedical Engineering, University of michigan, ann arbor, mI, 48109. m. o’donnell is with the department of bioengineering, University of Washington, seattle, Wa, 98195 (e-mail: odonnel@ engr.washington.edu). digital object Identifier 10.1109/TUFFc.2008.988