Optical Method for Characterising a Diffractive Surface and Apparatus for Implementing Such a Method

摘要

An optical method for characterizing a diffractive surface having a crystal grain structure, including the steps of: a) successively illuminating said surface with a plurality of light beams (Fi) having propagation directions inclined by a same angle Θ; relative to the normal to the surface and of which the projections on the surface form azimuth angles φ{umlaut over (ι)} that are different relative to a reference direction; b) acquiring an image of the surface corresponding to each of the light beams; and c) digitally processing images to obtain at least one item of information on at least one property of the surface chosen from: the grain structure, texture and level of ordering thereof. An optical head (TO) and apparatus for implementing such a method.

主权项

1. A method for characterizing a diffracting surface having a grain structure, comprising the steps:
a) illuminating in succession said surface with N>1 light beams (Fij) having propagation directions inclined at the same angle θi to the normal to the surface and the projections of which onto the surface make different azimuthal angles φij to a reference direction; b) acquiring an image of said surface in correspondence with each of said light beams in a given acquisition direction; and c) digitally processing said images to obtain at least one piece of information on at least one property of said surface, chosen from: its grain structure, its texture and its degree of order; wherein said step c) comprises determining, for each point of said surface corresponding to a pixel of said images, an average azimuthal angle of a range of azimuthal angles φij for which said point appears bright when it is observed in said acquisition direction.