Patent ID: 7768660

Claim:
A method of non-destructively investigating properties of a film coating being formed on, or present on an inner surface of a tube shaped system comprising the steps of: practicing steps a and b simultaneously or in either order; a) providing a tube shaped sample comprising outer and inner surfaces, said tube shaped sample having a film coating present on its inner surface; b) providing a system for causing a beam of electromagnetic radiation to impinge upon the outer surface of said tube shaped system at an oblique angle of incidence, and a detector situated to receive a component thereof reflected from the interface between said inner surface of said tube shaped sample and said film coating present thereupon; c) collecting and analyzing said electromagnetic radiation reflected from the interface between said inner surface of said tube shaped sample and said film coating present thereupon, to determine the optical constants and/or thickness of said film coating; said method further comprising performing at least one selection from the group consisting of: storing at least some data provided by said data detector in machine readable media; analyzing at least some of the data provided by said detector and storing at least some of the results of said analysis in machine readable media; displaying at least some data provided by said detector by electronic and/or non-electronic means; analyzing at least some of the data provided by said detector and displaying at least some of the results of said analysis by electronic and/or non-electronic means; causing at least some data provided by said detector to produce a signal which is applied to provide a concrete and tangible result; analyzing at least some of the data provided by said detector and causing at least some thereof to produce a signal which is applied to provide a concrete and tangible result.