Abstract: Quantitative phase imaging device having an imaging optical system for imaging an object in an image plane, a light source for emitting light radiation over the Fourier plane of the imaging optical system, an optical spatial filter in the Fourier plane, having an area of least attenuation and an area of greatest attenuation, a wavefront sensor for measuring, in the image plane, the intensity and the phase of the light radiation which has passed through the imaging optical system and of which at least part has interacted with the object, in order to quantify the phase induced by the object, the light source, the imaging optical system and the optical spatial filter being such that, when the object is absent, the light radiation is focused on the area of greatest attenuation.