Time resolved three-dimensional acousto-optic imaging of thick scattering media

Abstract

Acousto-optic imaging is based on light interaction with focused ultrasound in a scattering medium. Thanks to photorefractive holography combined with pulsed ultrasound, we perform a time-resolved detection of ultrasound-modulated photons in the therapeutic window (780 nm). A high-gain SPS:Te crystal is used for this purpose and enables us to image through large optical thickness (500 mean free paths). We are able to generate three-dimensional (3D) acousto-optic images by translating a multielement ultrasound probe in only one direction. A 3D absorbing object is imaged through a 3 cm thick phantom.

Light fields in complex media: Mesoscopic scattering meets wave control

“…However, due to fabrication imperfections and bendings, the ideal linearly polarized (LP) modes are not in general the eigenmodes of the system: The eigenmodes of a large-core MMF tend to be different from the ideal case. Nonetheless, it is possible to generate the so-called "principal modes" of an MMF (Fan and Kahn, 2005;Shemirani et al, 2009), which are unaffected by modal dispersion to first order of frequency variation. Their design principle bears very strong similarities with the eigenstates of the Wigner-Smith time-delay matrix described in section II.C (a detailed comparison between principal modes and so-called "particle-like states" will be provided in section V.C).…”

“…In particular, since the different transverse mode profiles also result in mode-specific longitudinal velocities it is tempting to think that the fiber modes are the suitable modes for avoiding dispersion in the fiber. It turns out, however, that this is generally not the case and that such a dispersion-free basis is rather given through the eigenbasis of the time-delay operator (Fan and Kahn, 2005;Poole and Wagner, 1986).…”

Phospholipid/carbocyanine dye-shelled microbubbles as ultrasound-modulated fluorescent contrast agents

“…An US-modulated beacon of light has the potential to enable optical detection at the spatial resolution of US (~1 mm), beyond sub-millimeter depths 12 . The sensitivity of fluorescence will allow the discrimination of a small signal of interest from a large background.…”

Experimental study of z resolution in acousto-optical coherence tomography using random phase jumps on ultrasound and light

“…This change of optical wavelength involves the use of other PR crystals (as SPS:Te, ZnTe, BSO) whose development is in progress [21,28]. In practice, this is very difficult to realize at λ 1064 nm because of water absorption.…”