Patent ID: 6856393

Claim:
A method of measuring a nonlinearity profile of a sample, the method comprising: providing a sample having at least one sample surface and having a sample nonlinearity profile along a sample line through a predetermined point on the sample surface, the sample line oriented perpendicularly to the sample surface; measuring a Fourier transform of the sample nonlinearity profile; providing a reference material having at least one reference surface and having a reference nonlinearity profile along a reference line through a predetermined point on the reference surface, the reference line oriented perpendicularly to the reference surface; obtaining a Fourier transform of the reference nonlinearity profile; forming a first composite sample having a first composite nonlinearity profile by placing the sample and the reference material proximate to one another in a first configuration with the sample line substantially collinear with the reference line; measuring a Fourier transform of the first composite nonlinearity profile; forming a second composite sample having a second composite nonlinearity profile which is inequivalent to the first composite nonlinearity profile by placing the sample and the reference material proximate to one another in a second configuration with the sample line substantially collinear with the reference line; measuring a Fourier transform of the second composite nonlinearity profile; and calculating the sample nonlinearity profile using the Fourier transforms of the sample nonlinearity profile, the reference nonlinearity profile, the first composite nonlinearity profile, and the second composite nonlinearity profile.