Patent ID: 6286370
Filing Date: 2001-09-11
Classification: G01N

Abstract:
A method for detecting materials on metal surfaces, which comprises the steps of:(a) applying sinusoidal vibrational excitation normal to the surface of the metal opposite the surface thereof to be investigated for deposits over a range of frequencies such that the wavelength of the sound waves induced in the metal is less than the thickness of the metal, and within which a standing-wave pattern is established;(b) measuring the amplitude and/or the peak width of at least one feature in the standing-wave pattern in approximately the region wherein the sinusoidal vibrational excitation is applied to the metal surface; and(c) comparing the measured amplitude and/or the measured peak width of the at least one feature in the standing-wave pattern with the amplitude and/or peak width of the corresponding feature in the standing-wave pattern of the uncoated metal, whereby the presence of materials on the metal surface is detected.