Method for determining the state of a cell

A method for determining a state of a cell, the cell being placed in a sample, the method comprising:

• illuminating the sample using a light source, the light source producing an incident light wave propagating towards the sample along a propagation axis;
• acquiring, using a matrix-array photodetector, a single image of the sample, the sample being placed between the light source and the matrix-array photodetector such that the matrix-array photodetector is exposed to a light wave comprising interference between the incident light wave and a diffraction wave produced by the cell;
• identifying a position of the cell in a plane parallel to a detection plane in which the matrix-array photodetector lies;
• applying a digital reconstruction algorithm to the single acquired image, to determine at least one characteristic quantity of the light wave to which the matrix-array photodetector is exposed, at the position of the cell, at a plurality of reconstruction distances from the matrix-array photodetector along the propagation axis, the digital reconstruction algorithm comprising performing a convolution product based on the acquired image and a propagation operator, the propagation operator describing the propagation of the light between the matrix-array photodetector and each reconstruction distance;
• obtaining a profile representing a variation of the characteristic quantity as a function of the distance along the propagation axis, the profile being obtained using the single acquired image;
• and
• classifying the cell depending on the profile, the classification allowing the state of the cell to be determined from among preset states.