Nuclear magnetometers of the type making use of a high frequency pumping on an electronic transition

Claim 1

IN A DEVICE FOR MEASURING THE INTENSITY OF A MAGNETIC FIELD AND COMPRISING AT LEAST ONE VESSEL INCLUDING A SAMPLE OF MATTER CONTAINING A FIRST SYSTEM OF SPINS HAVING IN SUCH A FIELD A RESONANCE LINE SATURABLE AT THE FIRST FREQUENCY BY AN ELECTRO-MAGNETIC FIELD PRODUCED IN SAID VESSEL AND A SECOND SYSTEM OF SPINS COUPLED WITH THE FIRST SYSTEM SO THE SATURATION OF THIS LINE PRODUCES A POLARIZATION OF THE SPINS OF THE SECOND SYSTEM AND INCREASES THE INTENSITY OF THE SIGNAL OF PRECESSION OF SAID SPINS OF THE SECOND SYSTEM ABOUT THE DIRECTION OF THE MAGNETIC FIELD TO BE MEASURED AT A SECOND FREQUENCY LOWER THAN SAID FIRST FREQUENCY AND PROPORTIONAL TO THE INTENSITY OF SAID MAGNETIC FIELD TO BE MEASURED, WHICH FREQUENCY IS MEASURED AFTER DETECTION OF SAID SIGNAL, THE COMBINATION WITH SAID VESSEL OF AN ELECTRIC COAXIAL LINE INCLUDING AN INTERNAL CONDUCTOR AND AN EXTERNAL CONDUCTOR ARRANGED TO HOUSE SAID VESSEL BETWEEN THEM, SAID CONDUCTORS BEING SHORTCIRCUITED AT ONE OF THEIR ENDS, THE LENGTH OF SAID COAXIAL LINE BEING AT MOST ONE TENTH OF THE WAVELENGTH IN SAID MATTER AT SAID FIRST FREQUENCY, MEANS AT THE OTHER ENDS OF SAID CONDUCTORS FOR ENERGIZING SAID COAXIAL LINE AT SAID FIRST FREQUENCY, SAID MEANS INCLUDING A HIGH FREQUENCY GENERATOR AND A TUNING CAPACITOR CONNECTED WITH SAID CONDUCTORS SO AS TO CONSTITUTE THEREWITH A CIRCUIT TUNED TO SAID FIRST FREQUENCY, THE REGION OF THE SPACE BETWEEN SAID CONDUCTORS WHERE SAID VESSEL IS LOCATED CORRESPONDING TO AN ANTINODE OF THE VARIATION ALONG THE AXIS OF SAID COAXIAL LINE OF THE TRANSVERSE MAGNETIC FIELD PRODUCED BY SAID ENERGIZING MEANS, ANS AT LEAST ONE COIL MOUNTED AROUND SAID COAXIAL LINE FOR DETECTING SAID SIGNAL OF PRECESSION.