Fourier magnitude of the field incident on a random scattering medium from spatial speckle intensity correlations

Imaging Hidden Objects with Spatial Speckle Intensity Correlations over Object Position

We present a coherent optical method for wavelength-resolution imaging of moving objects hidden within thick randomly scattering media. Spatial speckle intensity correlations as a function of object position are shown to provide access to the spatially dependent dielectric constant of the moving object. This speckle correlation imaging method yields field-based information previously inaccessible in heavily scattering environments. Proof of concept experimental results show excellent agreement with the theory. This new imaging approach will be valuable in high resolution imaging in tissue and other scattering environments where natural motion occurs or the object position can be controlled.

Imaging optical fields through heavily scattering media

Coherent imaging and communication through or within heavily scattering random media has been considered impossible due to the randomization of the information contained in the scattered electromagnetic field. We report a remarkable result based on speckle correlations over incident field position that demonstrates that the field incident on a heavily scattering random medium can be obtained using a method that is not restricted to weak scatter and is, in principle, independent of the thickness of the scattering medium. Natural motion can be exploited, and the approach can be extended to other geometries. The near-infrared optical results presented indicate that the approach is applicable to other frequency regimes, as well as other wave types. This work presents opportunities to enhance communication channel capacity in the large source and detector number regime, for a new method to view binary stars from Earth, and in biomedical applications.