A method for characterizing a particle (10 p ) present in a sample , the sample lying between an image sensor and a light source , the image sensor lying in a detection plane (P 0 ), the method comprising the following steps: a) illuminating the sample with the light source, the light source emitting an incident light wave that propagates along a propagation axis (Z); b) acquiring an image of the sample ( I 0 ) with the image sensor , the image comprising a plurality of elementary diffraction patterns, each elementary diffraction pattern corresponding to one particle; c) on the basis of the acquired image ( I 0 ), reconstructing a complex image ( A 10 ) representative of a complex amplitude of the exposure light wave on at least one reconstruction surface (P 10 ) passing through the sample, this reconstruction being achieved by implementing an iterative reconstruction algorithm, the algorithm comprising, in each iteration, updating a phase of the exposure light wave in the detection plane (P 0 ) or on the reconstruction surface (P 10 ); d) selecting a region of interest ( ROI i ) of the complex image, the selected region of interest corresponding to a particle of interest (10 p,i ); e) forming a complex image ( A 10,i ) extracted from the region of interest ( ROI i ) selected in step d); f) applying a propagation operator (h) to the extracted complex image ( A 10, i ) formed in step e), so as to obtain, in at least one propagation plane, an elementary diffraction pattern ( A 0, i ) of the particle selected in step c), such that the elementary diffraction pattern obtained is isolated from elementary diffraction patterns of other particles present in the sample; g) characterizing the particle of interest (10 p,i ) depending on the elementary diffraction pattern ( A 0, i ) resulting from step f). a) illuminating the sample with the light source, the light source emitting an incident light wave that propagates along a propagation axis (Z); b) acquiring an image of the sample ( I 0 ) with the image sensor , the image comprising a plurality of elementary diffraction patterns, each elementary diffraction pattern corresponding to one particle; c) on the basis of the acquired image ( I 0 ), reconstructing a complex image ( A 10 ) representative of a complex amplitude of the exposure light wave on at least one reconstruction surface (P 10 ) passing through the sample, this reconstruction being achieved by implementing an iterative reconstruction algorithm, the algorithm comprising, in each iteration, updating a phase of the exposure light wave in the detection plane (P 0 ) or on the reconstruction surface (P 10 ); d) selecting a region of interest ( ROI i ) of the complex image, the selected region of interest corresponding to a particle of interest (10 p,i ); e) forming a complex image ( A 10,i ) extracted from the region of interest ( ROI i ) selected in step d); f) applying a propagation operator (h) to the extracted complex image ( A 10, i ) formed in step e), so as to obtain, in at least one propagation plane, an elementary diffraction pattern ( A 0, i ) of the particle selected in step c), such that the elementary diffraction pattern obtained is isolated from elementary diffraction patterns of other particles present in the sample; g) characterizing the particle of interest (10 p,i ) depending on the elementary diffraction pattern ( A 0, i ) resulting from step f). <EOS>