Patent ID: 8160201

Claim:
A method for characterization of an element ( 1 , 21 ), the element being a substantially spherical particle which comprises a plurality of layers ( 5 , 7 , 9 , 11 ) which are substantially spherical, substantially concentric and superimposed, said superimposed layers ( 5 , 7 , 9 , 11 ) being separated from each other by means of substantially spherical interfaces, wherein the method comprises at least the following steps: illuminating the entire element ( 1 , 21 ) with radiation ( 15 ) emitted from an x-ray source ( 13 ), in such a way that some x-rays are transmitted through all the superimposed layers successively; acquiring on a detector ( 17 ) radiation ( 23 ) transmitted through the element ( 1 , 21 ), this transmitted radiation forming on the detector ( 17 ) an experiment image of the element ( 1 , 21 ), said experiment image being obtained by absorption of incident x-rays through the element, said experiment image being formed substantially by x-rays transmitted directly through the element, including the x-rays transmitted through all the superimposed layers, and showing the interfaces between the layers of the element, the detector ( 17 ) being placed at such a distance from the element ( 1 , 21 ) such that diffraction interference fringes appear superimposed on the experiment image at the interfaces between the layers ( 5 , 7 , 9 , 11 ); determining an approximate value of at least one physical characteristic of at least one specific layer ( 5 , 7 , 9 , 11 ) by means of calculation from the experiment image, the determination step being carried out by minimizing the deviation between the experiment image and a simulated image of at least a portion of the experiment image of the element ( 1 , 21 ).