Deflectometry method and associated system

A system for analyzing a reflective surface (S) through deflectometry, comprising:

• a display (Disp) arranged such that luminous images displayed on the display are reflected from said reflective surface (S), and configured to successively display n luminous images Ii indexed i, with n≥2, the n luminous images being obtained through n spatial shifts xi along a direction X of one and the same pattern M(x), a luminous image Ii(x,y) having a binarized luminous intensity that is obtained by dithering the pattern M(x−xi),
• imaging optics (IO) and a matrix detector (Det), the imaging optics being configured to image said surface (S) on said matrix detector, the matrix detector being configured to detect n images Idi, referred to as detected images, obtained by reflection of the n luminous images Ii from the reflective surface (S),
• a processing unit (PU) configured to:
• determine a function, referred to as object absolute phase function (fapS), based on the n detected images Idi, by applying a mathematical function g to said n detected images, the function g and the number of images n being determined such that the absolute phase function is bijective, the function g furthermore satisfying the relationship:
• g(k·M)=g(M), with k being any real value,
• compare the object absolute phase function (fapS) with what is referred to as a reference absolute phase function (fapMref), determined by replacing the surface (S) to be characterized with a plane mirror (Mref) defining what is referred to as a reference plane (Pref), and deduce therefrom information about the shape of said surface.