Patent ID: 7193710
Filing Date: 2007-03-20
Classification: G01J,G01N

Abstract:
1. A system for monitoring change in: the intensity of; and/or the ratio of and/or the phase between orthogonal components in; a spectroscopic beam of electromagnetic radiation which is caused by interaction with a material system; said system comprising at least one lens which is of multiple element construction and positioned so that beam of electromagnetic radiation transmits therethrough, wherein, at least two elements thereof are made from different materials, such that in use the focal length for each wavelength in a range of wavelengths is within an acceptable range of focal lengths; said at least one multiple element lens being characterized by at least one selection from the group consisting of: said system further comprising at least one compensator positioned so that beam of electromagnetic radiation transmits therethrough, said compensator being characterized by a selection from the group consisting of: said at least one compensator produces a retardence of between seventy-five (75) and one-hundred-thirty (130) degrees over a range of wavelengths defined by a selection from the group consisting of: said at least one compensator produces a retardation between thirty (30.0) and less than one-hundred-thirty-five (135) degrees over a range of wavelengths specified from MINW to MAXW by a selection from the group consisting of: