CONTACTLESS METHOD FOR DETERMINING THE THICKNESS OF A SAMPLE, CORRESPONDING SYSTEM

摘要

The invention relates to a method for measuring a Delta thickness of a sample (1), characterized in that said method comprises the steps according to which - a source (2) of a heat radiation beam (20) excites (S1) the sample (1) in a periodic fashion at a frequency (f), thereby causing the sample (1) to undergo periodic thermal excitation; - a sensor (3) measures (S2) a periodic thermal response on the part of the sample, in response to the periodic thermal excitation; - a processor (4) determines (S3) a phase shift (phi) between the periodic thermal excitation and the periodic thermal response; wherein the source (2) excites the sample for a plurality of frequencies (f) and wherein the processor (4) determines a phase shift for each frequency (f), thereby determining a plurality of phase shifts (phi); - the processor (4) - determines (S4) a minimum phase shift phimin (phi) by using the plurality of phase shifts determined in said manner, and - determines (S5) the Delta thickness of the sample (1) using the following formula: Delta = r0*g(phimin) where r0 is the heat radiation beam ray, and g is a function that depends on the type of heat radiation beam (20). The invention also relates to a system for implementing the method.