Optical characterization of tissue-simulating phantoms with microparticles by Digital Image Plane Holography

Abstract

Digital Image Plane Holography (DIPH) is a non-invasive optical technique which is able to recover the whole object wave. An object is illuminated and the diffused backscattered light is carried to a digital sensor by using a lens, where it interferes with a divergent reference wave with its origin in the lens aperture plane. Selecting each aperture image in the Fourier plane, the amplitude and the phase of the object beam are obtained. If two holograms are recorded at different times, after a small displacement, the reconstructed intensity distributions can be taken as a speckle field, while the phase difference distribution can be analyzed by an interferometric approach. In this work scattering media are investigated by using digital holography. The aim of this paper is to determine the viability of the technique to characterized optical properties of the sample. Different scattering media are modeled with different scattering properties. Each model generates a speckle pattern with different statistical properties (size, contrast, intensity). Both the visibility of the interferometric fringes and the properties of speckle pattern are related with optical properties of the media such as absorption and scattering coefficient. The ability to measure these properties makes the technique a promising method for biomedical applications.