Patent ID: 6658144
Filing Date: 2003-12-02
Classification: G01N,G06T,Y10S

Abstract:
A method of reconstructing an image of a structure having periodic variations in its index of refraction, the method comprising:projecting electromagnetic waves onto the structure at an angle corresponding to a predetermined diffraction order; measuring electromagnetic waves diffracted from the structure at that angle, wherein measuring includes determining a plurality of intensities DE1(N+1) through DE1(2N), wherein N is an integer greater than or equal to 1; and calculating a plurality of refractive terms n0 through nN, wherein calculating includes; calculating refractive term nN as a function of DE1(2N); calculating refractive term nNâˆ’1 as a function of nN and DE1(2Nâˆ’1); and calculating refractive term n1 as a function of DE1(N+1) and of n2 through nN.