Characterization of the angular memory effect of dynamic turbid media

The optical angular memory effect (AME) is a basic feature of turbid media and defines the correlation of speckles when the incident light is tilted. AME based imaging through solid scattering media such as ground glass and biomedical tissue has been recently developed. However, in the case of liquid media such as turbid water or blood, the speckle pattern exhibits dynamic time-varying characteristics, which introduces several challenges. The AME of the thick volume dynamic media is particularly different from the layer scatterers. In practice, there are more parameters, e.g., scattering particle size, shape, density, or even the illuminating beam aperture that can influence the AME range. Experimental demonstration of AME phenomenon in liquid dynamic media and confirm the distinctions will contribution to complete the AME theory. In this paper, a dual-polarization speckle detection setup was developed to characterize the AME of dynamic turbid media, where two orthogonal polarized beams were employed for simultaneous detection by a single CCD. The AME of turbid water, milk and blood were measured. The influence of thickness, concentration , particle size and shape, and beam diameter were analyzed. The AME increasement of upon the decrease of beam diameter was tested and verified. The results demonstrate the feasibility of this method for investigating the AME phenomenon and provide guidance for AME based imaging through scattering media.