Fig. 4: Experimental demonstration of super-resolution acousto-optic imaging (AOI) along the ultrasound propagation direction (y-axis).
From: Acousto optic imaging beyond the acoustic diffraction limit using speckle decorrelation
a target object, \(I(x,y)\), illuminated by a single speckle realization, \({S}_{i}(x,y)\), as imaged directly without the second scattering layer. b ultrasonically-tagged optical intensity distribution at the object plane, for one position (\({x}_{us},{y}_{us}\)) of the ultrasound focus, \(h(x,y)\), visualizing the ultrasound focus size. c ultrasound focus intensity as imaged directly without the target object, averaged over 40 speckle realizations. d AOI profile obtained by scanning the ultrasound focus along the dashed line in a from top to bottom: blue: conventional AOI (first cumulant); red: square-root of the second-order cumulant of the acousto-optic fluctuations, showing improved resolution; orange: third-order cumulant; black, dashed: cross-section of the target object, along the dashed line in a. Acoustic focus is \(260\ \upmu {\rm{m}}\) FWHM wide along scanning axis. scale-bars: \(280\ \upmu {\rm{m}}\).
