Device for detecting at least one object , the device including: - a light source configured to emit incident waves at a wavelength λ, - a detection volume intended to receive the object , and to receive the incident waves , - an image sensor positioned to receive at least scattered waves obtained by scattering incident waves on the object and reference waves corresponding to incident waves not scattered on the object , the sensor being configured to generate a holographic image based at least on the scattered waves and on the reference waves , - a computer data processing device configured to digitally reconstruct the object based at least on the holographic image and the wavelength λ, characterised in that the device also comprises at least one support comprising patterns organised to form at least one periodic diffraction grating having a pitch P, such that λ/2≤ P ≤2λ, so that the scattered waves collected by the sensor comprise: - waves from the source which were scattered by the object without being diffracted by the at least one diffraction grating , and - waves from the source which were both diffracted by the at least one diffraction grating and scattered by the object , the reference waves being incident waves having or not been diffracted by the diffraction grating , and wherein the computer device is configured to digitally reconstruct the object based on at least the holographic image , of wavelength λ and with a distance Z1 between the support and the image sensor , the distance Z1 preferably been taken along a propagation axis z of the incident wave . - a light source configured to emit incident waves at a wavelength λ, - a detection volume intended to receive the object , and to receive the incident waves , - an image sensor positioned to receive at least scattered waves obtained by scattering incident waves on the object and reference waves corresponding to incident waves not scattered on the object , the sensor being configured to generate a holographic image based at least on the scattered waves and on the reference waves , - a computer data processing device configured to digitally reconstruct the object based at least on the holographic image and the wavelength λ, characterised in that the device also comprises at least one support comprising patterns organised to form at least one periodic diffraction grating having a pitch P, such that λ/2≤ P ≤2λ, so that the scattered waves collected by the sensor comprise: - waves from the source which were scattered by the object without being diffracted by the at least one diffraction grating , and - waves from the source which were both diffracted by the at least one diffraction grating and scattered by the object , - waves from the source which were scattered by the object without being diffracted by the at least one diffraction grating , and - waves from the source which were both diffracted by the at least one diffraction grating and scattered by the object , the reference waves being incident waves having or not been diffracted by the diffraction grating , and wherein the computer device is configured to digitally reconstruct the object based on at least the holographic image , of wavelength λ and with a distance Z1 between the support and the image sensor , the distance Z1 preferably been taken along a propagation axis z of the incident wave . <EOS>