Patent ID: 8600703

Claim:
A method of compensating a sample characterizing data set for system drift during data acquisition, from a sample, comprising, in the recited order, the steps of: a) providing a system comprising: a source of a single required beam of electromagnetic radiation; a sample supporting stage; means for controlling where said single required beam of electromagnetic radiation from said source impinges on a sample placed on said stage; and a detector of electromagnetic radiation which exits said sample; b) causing the single required beam of electromagnetic radiation to impinge on a first position on a sample placed on said sample supporting stage, so that it interacts therewith and enters said detector, so that said detector provides as output, a first single data point in a brief period of time; c) causing said single required beam of electromagnetic radiation to impinge on a second, different from said first position on said sample on said sample supporting stage, so that it interacts therewith and enters said detector, so that said detector provides as output, a plurality of data points over time; and producing a plot of said plurality of data points as a function of time; d) causing said single required beam of electromagnetic radiation to again impinge on said first position on said sample on said sample supporting stage, so that it interacts therewith and enters said detector, so that said detector provides as output, a second single data point in a brief period of time; and producing a plot of said first and second data points acquired from said first position on said sample in steps b and d as a function of time; e) determining from said first and second data points acquired from said first position on said sample in steps b and d data acquisition system drift if said plot thereof presents with an overall non-zero slope; and f) determining from said plurality of data points acquired in step c sample drift caused by said single required beam of electromagnetic radiation-sample interaction, when said plot thereof presents with an overall non-zero slope as a function of time; said method further comprising: g) if the first and second data points acquired from said first position on said sample in steps b and d are different, then compensating said plurality of data points acquired from the second position in step c for the identified system drift during data acquisition; to the end that a sample characterizing data set which is compensated for system drift during data acquisition is achieved.