Patent ID: 7272510
Filing Date: 2007-09-18
Classification: G01N

Abstract:
1. A method of providing a correction for a slave instrument, the slave instrument measuring properties of an object by exposing the object to electromagnetic radiation in at least two spectral ranges and obtaining one or more object responses thereto, the responses being based on detecting at least one of attenuation, reflection and scattering of the electromagnetic radiation in or from the object by use of one or more detectors, the responses obtained in a form where they express properties either directly or via a transformation, said method of correction comprising: obtaining, for a plurality of stable objects, a set of responses, comprising one or more pairs of related responses (Q wherein a pair of related responses (Q wherein each element in the corresponding pair of responses (Q determining, based on the sets of responses, a correcting function, the correcting function being a functional relationship between a ratio of related responses of the master instrument and a sum of a plurality of terms, each term being a product of a correcting coefficient (B storing the first set of correcting coefficients (B initially measuring the plurality of stable objects on the master instrument to obtain the set of responses (Q initially storing the set of response (Q