Patent ID: 7030380
Filing Date: 2006-04-18
Classification: G01N

Abstract:
1. An apparatus comprising: a) an IR transparent internal reflectance element (IRE) with at least one essentially flat surface and at least one convex surface that can contact a fluid, b) at least two IR light paths of different frequencies with emitted light from one or more source entering a flat surface of the IRE, internally reflecting at least once from a convex surface of the IRE that can contact a fluid, exiting a flat surface of the IRE, and being received at one or more detectors; wherein a determined frequency of the different frequencies of a said light path is determined by at least one of the following: a) the light path's source only emits light at the determined frequency, b) each of the light path's detector only receives light at the determined frequency, e) and an optical filter of the determined frequency is placed between the light path's source and the detector, and c) combinations thereof, and c) electronics to power the light paths, independently monitor the amount of light received for each light path, and communicate information relevant to the monitored light reception wherein the number of reflections that a said light path makes from at least one convex surface of the IRE, which can contact the fluid, is determined by at least one of the following a) a shape of the IRE, b) a surface property of the IRE, c) a relative position at a said IRE flat surface that the light path's IR source light enters the IRE, d) a relative position at a said IRE flat surface that the light path's detector receives light that exits the IRE, and e) combinations thereof.