Optical coherence-domain reflectometry and laser-based ultrasound detection have been combined with the use of adaptive optics to detect ultrasound through turbid media. The dynamic hologram in a photorefractive quantum-well device performs as a coherence gate that eliminates multiply scattered background. Quadrature homodyne detection conditions are selected by the choice of center wavelength of the pulse spectrum, requiring no active stabilization or feedback. A depth resolution of 30 μm was achieved, with a pulse duration of nominally 120 fs for ultrasound detection through turbid media up to optical thicknesses of 11 mean free scattering lengths.
© 2003 Optical Society of America
(120.2880) Instrumentation, measurement, and metrology : Holographic interferometry
(120.2920) Instrumentation, measurement, and metrology : Homodyning
(160.5140) Materials : Photoconductive materials
(170.7170) Medical optics and biotechnology : Ultrasound
P. Yu, L. Peng, D. D. Nolte, and M. R. Melloch, "Ultrasound detection through turbid media," Opt. Lett. 28, 819-821 (2003)