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Abstract-In this work, we present a Photorefractive Digital Holographic Microscopy (PRDHM) technique based on the writing-reading holographic process in photorefractive Bi 12 TiO 20 (BTO) crystal using the numerical reconstruction of the phase and amplitude image performed by a Digital Holographic Microscopy (DHM) method. We demonstrate that a holographic reconstructed image by diffraction process in photorefractive BTO crystal can be combined with a second reference beam to form a hologram in CCD plane in a DHM setup. The experimental results in a glass slide resolution target and thin film structure was obtained, where, amplitude, phase and 3D phase images are calculated performing digital reconstruction. This technique presents potentials possibilities to obtain 3D phase image of the microdevices for dynamic holography applications.Index Terms-holography; microscopy; non-destructive testing; photorefractive materials. I. INTRODUCTIONPhotorefractive holography is increasingly being used for quantitative measurements of the amplitude and phase of the objects waves in static and dynamic process [1][2][3][4][5][6][7]. In the photorefractive holography, the holographic recording medium is a photorefractive (PR) material. In PR crystals the holographic grating recording are characterized by following light-induced mechanisms: photorefractive (PR) effect, thermo-optic refractive index modulation or photochromic effect [1]. The PR effect consists on the refractive index modulation through charge carriers photo-induction and linear electro-optic effect; the refractive index modulation by thermo-optic effects is due to temperature gradients on the crystal surface; and the photochromic effect is caused by absorption coefficient modulation for high light intensities. These holographic recording materials present advantages like in situ self-processing of recording medium, indefinite reusability, high resolution and low response time. Moreover, PRCs do not present fatigue in dynamic and reversible processes. In Digital Holography by calculating the complex optical field of an image, the amplitude and phase of the optical field are available for direct manipulation [8][9][10][11][12]. The applications of digital holography to microscopy are particularly advantageous because a single hologram records the information of a three-dimensional object space. These advantages have been noted since early in the development of digital holography and applied to imaging analysis of microstructures and biological microscopy [9-12] using CCD sensor as holographic detector. In off-axis holography the angle of incidence of the reference beam is chosen so that when the hologram is reconstructed, the zero order light may be spatially separated from the diffracted holographic reconstruction. The method of offaxis holography involves a high spatial-frequency fringe pattern that must be sufficiently sampled by the CCD, the spatial resolution of the CCD is an important parameter.Recently, some works present the combination of the photorefractiv...