1. A method for imaging an object, the method comprising: (a) applying a structured periodic illumination to the object a plurality of times with a plurality of phase shifts in the structured illumination; (b) taking a plurality of images of the object corresponding to the plurality of phase shifts; (c) estimating the plurality of phase shifts by determining a phase of a peak of a Fourier transform of each of the images taken in step (b); and (d) reconstructing an image of the object using the plurality of images taken in step (b) and the plurality of phase shifts estimated in step (c).