Multi-range temperature measuring apparatus

Claim 1

A SENSING HEAD FOR AN INSTRUMENT OF THE CLASS DESCRIBED COMPRISING A BOX, A LENS TUBE ON THE BOX OPENING INTO THE BOX, AN EYE-PIECE ON THE BOX OPENING INTO THE BOX OPPOSITE THE LENS TUBE, A BEAM SPLITTER IN THE BOX INTERPOSED BETWEEN THE LENS TUBE AND THE EYE-PIECE ARRANGED TO ENABLE PART OF THE LIGHT ENTERING THE BOX THROUGH THE LENS TUBE TO PASS DIRECTLY TO THE EYE-PIECE WHEREBY THE INSTRUMENT MAY BE AIMED BY LOOKING THROUGH THE EYE-PIECE AND LENS TUBE TO THE OBJECT TO BE OBSERVED, A LIGHT PIPE AT RIGHT ANGLES TO THE LINE OF SIGHT FROM THE EYE-PIECE THROUGHT THE LENS TUBE, THE BEAM SPLITTER AND LIGHT PIPE BEING ARRANGED TO TRANSMIT PART OF THE ENTERING LIGHT FROM THE LENS TUBE INTO THE LIGHT PIPE, A PHOTOMULTIPLIER TUBE AND ENCLOSURE THEREFOR IN THE BOX, THE LIGHT-SENSITIVE AREA OF SAID TUBE BEING IN THE PATH OF LIGHT TRANSMITTED BY THE LIGHT PIPE, A FILTER DISK MOUNTED FOR ROTATION IN THE BOX BETWEEN THE LIGHT PIPE AND THE PHOTOMULTIPLIER TUBE AND IN THE PATH OF LIGHT TRANSMITTED FROM THE PIPE, THE DISK BEING OF A UNIFORM COLOR FOR PASSING A BAND FREQUENCY OF LIGHT ENERGY WITHIN THAT COLOR OF THE SPECTRUM AND HAVING INDEPENDENT FILTERS OF DIFFERENT COLORS FOR PASSING SELECTED BAND FREQUENCIES OF LIGHT ENERGY, EACH INDEPENDENT FILTER BEING POSITIONED ORBITALLY WITHIN THE DISK AT A RADIAL DISTANCE SUCH THAT TE ROTATION OF THE DISK BETWEEN THE LIGHT PIPE AND PHOTO-MULTIPLIER TUBE ALTERNATELY PASSES LIGHT ENERGY FROM THE PIPE TO THE PHOTOMULTIPLIER TUBE OF A BAND FREQUENCY WITHIN THE UNIFORM COLOR BAND OF THE SPECTRUM AND THE COLOR BAND OF ONLY ONE OF THE INDEPENDENT FILTERS FOR EACH REVOLUTION OF THE DISK, MEANS FOR POSITIONING THE DISK FOR SELECTIVELY POSITIONING ONE OF THE ORBITAL INDEPENDENT FILTERS IN THE LIGHT PATH BETWEEN THE PIPE AND PHOTO-MULTIPLIER TUBE FOR ROTATION, AND MEANS IN THE BOX FOR ROTATING THE DISK.