Fluid analysis by infrared absorption

Claim 1

AN INFRARED ABSORPTION ANALYZER FOR MEASURING ONE COMPONENT OF A FLUID MIXTURE WHERE THAT COMPONENT HAS A DEFINED INFRARED ABSORPTION BAND THAT IS SUBSTANTIALLY OVERLAPPED BY THE ABSORPTION BAND OF A MASKING COMPONENT OF THE MIXTURE AND WHERE THE MASKING COMPONENT ALSO HAS A DEFINED INFRARED ABSORPTION BAND THAT IS OUTSIDE OF THE ABSORPTION BAND OF THE COMPONENT TO BE MEASURED, SAID ANALYZER COMPRISING A SOURCE OF INFRARED RADIATION THAT INCLUDES A FIRST BAND OF INFRARED RADIATION COMPRISING AT LEAST PART OF THE OVERLAPPING PORTIONS OF THE ABSORPTION BANDS OF THE COMPONENT TO BE MEASURED AND OF THE MASKING COMPONENT AND ALSO INCLUDES A SECOND BAND OF INFRARED RADIATION COMPRISING AT LEAST PART OF A NON-OVERLAPPING PORTION OF THE ABSORPTION BAND OF THE MASKING COMPONENT ALONE, AN ANALYTICAL FILTER AND A REFERENCE FILTER FOR RECEIVING SEPARATELY BEAMS OF RADIATION EMITTED FROM THE SOURCE, THE ANALYTICAL FILTER BEING TRANSPARENT TO AT LEAST A PART OF SAID FIRST BAND BUT TO SUBSTANTIALLY NONE OF SAID SECOND BAND OF RADIATION AND THE REFERENCE FILTER BEING TRANSPARENT TO AT LEAST A PART OF SAID SECOND BAND BUT TO SUBSTANTIALLY NONE OF SAID FIRST BAND OF RADIATION, MEANS FOR EXPOSING THE MIXTURE TO BE ANALYZED IN THE OPTICAL PATH OF SAID RADIATION BEAMS, AND RADIATION RESPONSIVE MEANS FOR RECEIVING AND MEASURING BOTH THE RADIATION TRANSMITTED THROUGH THE MIXTURE AND THE ANALYTICAL FILTER AND THE RADIATION TRANSMITTED THROUGH THE MIXTURE AND THE REFERENCE FILTER; SAID RADIATION RESPONSIVE MEANS BEING LEAD SULFIDE PHOTO RESISTORS MOUNTED ON AN ALUMINUM HEAT SINK, SAID HEAT SINK BEING IN CONTACT WITH A HEATER MEANS TO MAINTAIN UNIFORM TEMPERATURE OF THE RADIATION RESPONSIVE MEANS, SAID HEATER MEANS BEING AN ELECTRICAL RESISTANCE ELEMENT MOUNTED ON A CERAMIC SUBSTRATE.