Patent ID: 9594024
Date: 2017-03-14
CPC Classifications: G01J,G01N,G02B

Claim:
1. A method for correcting an optical signal produced by a sample comprising the following steps: illuminating a surface of the sample by a first light beam, produced by a first light source, said first light source being coupled to a first optical system, focusing said first light beam in an object focal plane of the first optical system, said object focal plane being situated, in the sample, at a measuring depth z from the surface of the sample; and measuring, with a first photodetector, of a first optical signal backscattered by the sample in response to the first light beam, the first photodetector producing a first measured signal representative of said first optical signal, a spatial filter being interposed between the first optical system and the first photodetector, the spatial filter comprising a window which transmits said first optical signal towards said first photodetector, the window being disposed in a conjugate focal plane of the object focal plane of the first optical system, wherein the method also comprises the following steps: determining an optical scattering property of the sample; applying a correction function to the first measured signal so as to generate a first corrected signal, said correction function taking into account said optical scattering property, and wherein the determination of the optical scattering property of the sample further comprises: performing a second illumination of a surface of the sample with a second light beam, so as to form, on said surface, an elementary illumination zone, corresponding to the part of said surface illuminated by said second light beam; detecting N second optical signals, backscattered by the sample, each second optical signal emanating from the surface of the sample at a backscattering distance from said elementary illumination zone, N being an integer greater than or equal to 1, so as to form as many second detected signals; and determining at least one optical scattering property of the sample, by comparison between: